WO2015119693A2

WO2015119693A2 - Structural ballistic resistant apparatus

Info

Publication number: WO2015119693A2
Application number: PCT/US2014/065214
Authority: WO
Inventors: Eric B. Strauss
Original assignee: Angel Armor, Llc
Priority date: 2013-11-12
Filing date: 2014-11-12
Publication date: 2015-08-13
Also published as: WO2015119693A3

Abstract

A structural ballistic resistant apparatus can provide protection against ballistic threats and can be configured to serve as a load-bearing structure. The structural ballistic resistant apparatus can include a stack of laminated ballistic resistant sheets. The structural ballistic resistant apparatus can include a structural composite layer covering and conforming to at least a portion of the laminated stack of ballistic resistant sheets and serving as a load-bearing structure. The structural composite layer can include a reinforcing fabric containing a cured matrix material.

Description

STRUCTURAL BALLISTIC RESISTANT APPARATUS

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims the benefit of U.S. Provisional Patent Application Nos. 61/903,353 filed November 12, 2013, 61/978,342 filed April 11, 2014, 62/012,959 filed June 16, 2014 and U.S. Patent Application No. 14/539,259 filed November 12, 2014, all of which are incorporated by reference in their entirety as if fully set forth in this description.

FIELD OF THE INVENTION

[0002] This disclosure relates to structural ballistic resistant apparatuses and systems and methods for manufacturing structural ballistic resistant apparatuses.

BACKGROUND

[0003] Ballistic resistant panels can safeguard people and property from ballistic threats, such as projectiles and blasts. For instance, ballistic resistant panels can be incorporated into vehicle doors and floors to prevent occupants and equipment from projectiles or shrapnel from improvised explosive devices. Ballistic resistant panels are often made of woven fabrics consisting of high performance fibers, such as aramid fibers. When struck by a projectile, such as a bullet, fibers in the woven fabric dissipate impact energy from the projectile by stretching and breaking, thereby providing a level of ballistic protection.

[0004] Existing ballistic resistant panels are often made of stacks of woven ballistic resistant sheets stitched together by a sewing process that often requires an industrial sewing machine. The level of ballistic protection provided by the panel is largely dictated by the types of fibers used in the individual woven ballistic resistant sheets, the number of woven ballistic resistant sheets, and the stitching patterns used to bind the woven ballistic resistant sheets into a panel. A wide variety of stitching patterns are used in existing panels, including quilt stitches, radial stitches, row stitches, and box stitches.

[0005] When a projectile strikes a panel made of a stack of woven ballistic resistant sheets that are bound by stitching, each woven ballistic resistant sheet dissipates a certain portion of the energy of the projectile as the projectile passes through each sheet. Within each woven ballistic resistant sheet, individual fibers stretch and break apart as the projectile penetrates the sheet. The impact energy absorbed by a struck fiber will be transferred and dissipated to nearby fibers at crossover points where the fibers are interwoven or bound by a stich. Individual stitches stretch and break apart as the projectile enters the panel, thereby dissipating impact energy from the projectile and acting as a sacrificial element of the panel.

[0006] Due to the sacrificial nature of the fibers and stitches, the panel will be severely damaged when struck by a projectile. Visual inspection of the panel will typically reveal significant damage to the woven ballistic resistant sheets and to stitches both at the impact location and the surrounding area. If a second projectile strikes the panel at or near the first impact location, the panel will not effectively stop the second projectile, and the second projectile will pass through the panel and into a person or property behind the panel. Therefore, existing panels do not provide reliable protection against multiple projectiles striking the panel in close proximity, which is a common threat posed by many automatic and semi-automatic weapons.

[0007] Military, civilian, and law enforcement vehicles can be equipped with armor plating to protect vehicle occupants from ballistic threats, such as projectiles or blasts. Armor plating is commonly made of steel, which is a heavy material. When steel plating is added to a vehicle, the weight of the vehicle increases significantly. To ensure adequate performance of the vehicle after installation of the steel plating, the suspension of the vehicle may need to be enhanced. Depending on the weight of the steel plating, the chassis of the vehicle may also need to be enhanced, for example, by welding additional structural members to the frame, which can be costly and labor-intensive. These modifications alter the appearance of the vehicle, making the vehicle easily identifiable as an armored vehicle by adversaries, which can jeopardize the safety of vehicle occupants and make the vehicle unfit for covert missions.

[0008] For at least the aforementioned reasons, existing ballistic resistant panels are not well-suited for combat environments or other applications where lightweight, multi-round capabilities are desirable.

BRIEF DESCRIPTIONS OF DRAWINGS

[0009] FIG. 1A shows a perspective view of a structural ballistic resistant apparatus having a first structural composite layer joined to a second structural composite layer to encase a laminated stack of ballistic resistant sheets.

[0010] FIG. IB shows a perspective cross-sectional view of the structural ballistic resistant apparatus of Fig. 1 A exposing the stack of laminated ballistic resistant sheets encased by the first structural composite layer and the second structural composite layer.

[0011] FIG. 1C shows a side cross-sectional view of a structural ballistic resistant apparatus of Fig. 1 exposing a stack of laminated ballistic resistant sheets bounded by the first structural composite layer and the second structural composite layer.

[0012] FIG. 2 shows a side cross-sectional view of a structural ballistic resistant apparatus exposing a stack of laminated ballistic resistant sheets having a top ballistic resistant sheet adjacent to a first structural composite layer and a bottom ballistic resistant sheet adjacent to a second structural composite layer.

[0013] FIG. 3 shows a side cross-sectional view of a structural ballistic resistant apparatus including a stack of laminated ballistic resistant sheets bounded by a first structural member made of a composite material and a second structural member made of a composite material and also bounded by a third structural member made of metal or ceramic and a fourth structural member made of metal or ceramic.

[0014] FIG. 4 shows a side cross-sectional view of a structural ballistic resistant apparatus including a stack of laminated ballistic resistant sheets bounded by a first structural member made of a composite material and a second structural member made of a composite material and also bounded by a third structural member made of metal or ceramic and a fourth structural member made of metal or ceramic.

[0015] FIG. 5 shows a side cross-sectional view of a structural ballistic resistant apparatus encased in a waterproof cover, the apparatus including a stack of laminated ballistic resistant sheets bounded by a first structural member made of a composite material and a second structural member made of a composite material and also bounded by a third structural member made of metal or ceramic.

[0016] FIG. 6 shows a side cross-sectional view of a structural ballistic resistant apparatus including a stack of laminated ballistic resistant sheets and a structural member made of metal or ceramic encased by a first structural member made of a composite material and a second structural member made of a composite material.

[0017] FIG. 7 shows a side cross-sectional view of a structural ballistic resistant apparatus including a stack of laminated ballistic resistant sheets and a structural member made of metal or ceramic encased by a first structural member made of a composite material and a second structural member made of a composite material.

[0018] FIG. 8 shows a side cross-sectional view of a structural ballistic resistant apparatus including a stack of laminated ballistic resistant sheets bounded by structural members made of metal or ceramic and encased by a first structural member made of a composite material and a second structural member made of a composite material.

[0019] FIG. 9 shows a side cross-sectional view of a structural ballistic resistant apparatus in the form of an I-beam. The structural ballistic resistant apparatus includes a stack of laminated ballistic resistant sheets bounded by a top structural member, a bottom structural member, a left side structural member, and a right side structural member.

[0020] FIG. 10 is a cross-sectional view of a structural ballistic resistant apparatus including a section of round tubing, a stack of laminated ballistic resistant sheets conformed over an outer surface of the round tubing, and a structural member made of a composite material conformed over the stack of laminated ballistic resistant sheets. [0021] FIG. 11 is a cross-sectional view of a structural ballistic resistant apparatus including a section of square tubing, a stack of laminated ballistic resistant sheets conformed over an outer surface of the square tubing, and a structural member made of a composite material conformed over the stack of laminated ballistic resistant sheets.

[0022] FIG. 12 is a perspective view of a stack of ballistic resistant sheets encased in a composite layer made of a reinforcing fabric and a matrix material. The stack and composite layer, along with corresponding release layers and breather layers, are located in an open condition of a variable volume container in accordance with a particular embodiment of a lamination method.

[0023] FIG. 13 is a perspective view of a stack of ballistic resistant sheets encased by a composite layer made of a reinforcing fabric and a matrix material. The stack and composite layer, along with corresponding release layers and breather layers, are located in a closed condition of an evacuated variable volume container in accordance with a particular embodiment of a lamination method.

[0024] FIG. 14 is a perspective view of a closed condition of the evacuated variable volume container located within a heated enclosure or heated and pressurized enclosure and containing the stack of ballistic resistant sheets encased by a composite layer, the composite layer being transformed from flexible reinforcing fabric containing a matrix material into a hard, structural composite layer due to curing of the matrix material as a result of the heating process.

[0025] FIG. 15 is a perspective view of an evacuated variable volume container located in a particular configuration of a press mold, the evacuated variable volume contained containing a stack of ballistic resistant sheets encased by a composite layer made of reinforcing fabric and a matrix material.

[0026] FIG. 16 is a perspective view of a closed condition of an evacuated variable volume container pressed between a first mold part and a second mold part of a press mold.

[0027] FIG. 17 is a perspective view of an evacuated variable volume container located in a particular configuration of a press mold, the evacuated variable volume contained containing a stack of ballistic resistant sheets encased by a composite layer made of reinforcing fabric and a matrix material.

[0028] FIG. 18 is a perspective view of a closed condition of the evacuated variable volume container pressed between a first mold part and a second mold part of a press mold to form the three-dimensional structural ballistic resistant apparatus shown in Figs. 22-24.

[0029] FIG. 19 is a perspective view of the closed condition of the evacuated variable volume container having reduced pressure within to consolidate a laminatable stack of ballistic resistant sheets to form a structural ballistic resistant apparatus.

[0030] FIG. 20 is a perspective view of an open condition of the variable volume container for removal of a structural ballistic resistant apparatus having a consolidated laminated stack of ballistic resistant sheets encased by a structural composite layer.

[0031] FIG. 21 is a perspective view of a structural ballistic resistant apparatus in the form of a flat sheet produced by a laminating method. [0032] FIG. 22 is a perspective view of a closed condition of an evacuated variable volume container having reduced pressure within to consolidate a laminatable stack to form a structural ballistic resistant apparatus.

[0033] FIG. 23 is a perspective view of an open condition of a variable volume container for removal of a structural ballistic resistant apparatus having a consolidated laminated stack of ballistic resistant sheets encased by a structural member.

[0034] FIG. 24 is a perspective view of a three-dimensionally formed structural ballistic resistant apparatus produced by a method in the form of a hollow hemisphere, the apparatus having a laminated stack of ballistic resistant sheets covered by a structural composite layer.

DETAILED DESCRIPTION

[0035] A structural ballistic resistant apparatus 100 can be a load-bearing structure that also provides protection from ballistic threats. The structural ballistic resistant apparatus 100 can include a laminated stack of ballistic resistant sheets and one or more structural members along exterior surfaces of the stack of ballistic resistant sheets or interspersed within the stack of ballistic resistant sheets. The term "member" as used herein can describe any suitable layer, strip, shell, sheet, rod, tube, beam, or portion having any suitable shape (e.g. flat, curved, or complexly curved) and any suitable dimensions. The material used in the one or more structural members can vary depending on an intended application of the structural ballistic resistant apparatus. For instance, where the purpose of the structural member is to bolster the stiffness of the structural ballistic resistant apparatus and improve the apparatus' ability to withstand torsional, compressive, or tensile forces without experiencing appreciable deflection or elongation, the structural member may be made of a carbon fiber composite material or a fiberglass composite material. In another example, where the purpose of the structural member is to bolster the stiffness of the apparatus as well as enhance ballistic performance of the apparatus, the structural member may be made of a metal or ceramic material. Suitable metals capable of enhancing ballistic performance of the apparatus include, for example, aluminum, steel, titanium, and magnesium. Suitable ceramics capable of enhancing ballistic performance of the apparatus include silicon carbide, boron carbide, zirconia toughened alumina, titanium diboride, and high-density aluminum oxide.

[0036] The structural ballistic resistant apparatuses 100 described herein can exhibit significantly higher ballistic performance than existing ballistic resistant panels. The apparatuses described herein experience significantly less back face deformation than existing panels when exposed to similar ballistic threats. Also, the apparatuses described herein provide improved multi-round capability over existing panels.

[0037] A method of manufacturing the ballistic resistant apparatuses 100 described herein can involve one or more steps, including arranging a plurality of ballistic resistant sheets into a stack, vacuum bagging the stack of ballistic resistant sheets, heating the stack of ballistic resistant sheets, applying pressure to the stack of ballistic resistant sheets, 3-D forming the stack of ballistic resistant sheets, and cooling a stack of ballistic resistant sheets. The apparatuses described herein can effectively serve as structural members in, for example, vehicles (e.g. automobiles, ships, aircraft), buildings, structures or systems (e.g. bridges, pipelines, antennas), or any other object requiring a member that has both structural and ballistic capabilities, as further described below. Wide-Ranging Applications

[0038] The structural ballistic resistant apparatuses 100 described herein can be used in a wide range of applications that require both structural support and the ability to dissipate impact energy from ballistic threats. The structural ballistic resistant apparatuses 100 described herein have a wide variety of applications, including, but not limited to, vehicle armor, protective cases for computers or other electronic devices, personal protective equipment (e.g. helmets, chest protectors, protective pads), barricades, oil and gas pipelines, oil and gas pipeline coverings, doors, wall inserts, military helmets, public speaking podiums, theater seats, airline seats, cockpit doors for aircraft, portable military dwellings, or boat or ship components (e.g. hulls, hatches, structural supports, periscopes, masts, and decking). The structural ballistic resistant apparatuses 100 described herein can also replace components that are purely structural.

[0039] The ballistic resistant panels 100 described herein can serve as spall liners in tanks and other armored vehicles to protect against, for example, the effects of high explosive squash head (HESH) anti-tank shells. Spall liners can serve as a secondary armor for occupants and equipment within an armored vehicle having a primary armor made of steel, ceramic, aluminum, or titanium. In the event of an impact or explosion proximate an outer surface of the armored vehicle, the spall liner can prevent or reduce fragmentation into the vehicle cabin, which is desirable, since fragmentation into the vehicle cabin can injure vehicle occupants. When used as a spall liner, the structural ballistic resistant apparatus 100 can be positioned between exterior steel armor plating of the military vehicle and the cabin of the vehicle. In other examples, the structural ballistic resistant apparatus 100 can serve as a body or chassis component of the vehicle (e.g. tank, MRAP, Humvee, light tactical vehicle).

[0040] The structural ballistic resistant apparatuses 100 described herein can be incorporated into vehicle doors, floors, firewalls, roofs, and seats to protect the vehicle, occupants, equipment, and ammunitions in the vehicle from projectiles. Due to their relative light weight and low cost, the structural ballistic resistant apparatuses 100 described herein can be also incorporated into consumer vehicles without significantly reducing fuel economy or increasing vehicle cost. In addition to protecting against ballistic threats, the panels may improve certain aspects of vehicle crash performance. In one example, a vehicle frame can include one or more sections of box tubing welded together to form the vehicle frame, and the box tubing can contain a laminated stack of ballistic resistant sheets disposed within an inner volume of the box tubing or on an outer surface of the tubing, as shown in Fig. 11, with a structural composite layer 505 disposed over the laminated stack of ballistic sheets. The structural composite layer 505 may increase the stiffness of the vehicle frame and may resist buckling of a section of tubing when the section is subjected to an axial compression, such as during a vehicle collision.

[0041] The structural ballistic resistant apparatuses 100 described herein can be used to protect commercial, governmental, or residential buildings (e.g. banks, homes, schools, office buildings, prisons, restaurants, laboratories, churches, and convenience stores) from ballistic threats. The structural apparatuses (e.g. panels) can be incorporated into walls, floors, or ceilings (e.g. in homes, banks, or law enforcement facilities). In one example, the apparatuses can be incorporated into a wall and can be concealed by or within drywall. In this way, the structural ballistic resistant apparatus 100 may not be visible and may not detract from the appearance of the wall, or be easily detected. The structural apparatuses 100 can be incorporated into manufactured (i.e. pre-made) walls that are delivered to a construction site, or the apparatus can be inserted into walls that are built on site. In another example, the structural ballistic resistant apparatus 100 can serve as a wall component and can include an exterior covering (e.g. drywall) that can be painted to look like a traditional wall in a home or office building. In this example, the structural ballistic resistant apparatus 100 may include one or more structural members (e.g. 110, 115, 120, or 125) that support the panel in an upright position and allow the apparatus to effectively support the weight of a roof, beam, or other structural member, located above the panel and transfer that weight to, for example, a floor or foundation of the building.

[0042] The structural ballistic resistant apparatuses 100 shown in Fig. 10 and 11 can each represent a cross-sectional view of a fuel tank. The fuel tank 100 can be a fuel tank incorporated into a vehicle (e.g. Humvee, MRAP, jet, airplane, or drone), a freestanding tank for an oil refinery, or a primary tank attached to a tanker truck. The fuel tank 100 can include an inner structural member 120 wrapped in a stack of laminated ballistic resistant sheets 8. The laminated stack of ballistic resistant sheets 8 can be covered by a structural member 110 that can be made of a composite material, such as a carbon fiber composite material or a fiberglass composite material. In some examples, the inner structural member 120 can be made of steel or aluminum or plastic.

[0043] The structural ballistic resistant apparatuses 100 shown in Figs. 10 and 11 can each represent a cross-sectional view of a fuselage of a submarine, airplane, satellite, or drone or the exterior shell of a missile, torpedo, or other weapon system. The fuselage 100 or weapon system 100 can include an inner structural member 120 wrapped in a stack of laminated ballistic resistant sheets 8. The laminated stack of ballistic resistant sheets 8 can be covered by a structural member 110 that can be made of a composite material, such as a carbon fiber composite material or a fiberglass composite material. In one example, the inner structural member 120 can be made of steel.

[0044] The structural ballistic resistant apparatus 100 described herein can form a pipeline (e.g. petroleum or gas pipeline) or tank capable of defending against ballistic threats. As shown in Fig. 10, a section of round tubing 120 (e.g. steel tubing) that is adapted to serve as a conduit for any type of liquid or gas (e.g. natural gas, oil, gasoline, or diesel fuel) can be encased with a plurality of UHMWPE ballistic resistant sheets 8 forming a laminated stack. The laminated stack of ballistic resistant sheets 8 can be covered by a structural member 110 that can be made of a composite material, such as a carbon fiber composite material or a fiberglass composite material.

[0045] The structural ballistic resistant apparatus 100 shown in Fig. 10 can include a section of steel pipeline with the structural ballistic resistant apparatus formed thereon. Alternately, the apparatus can be a panel that is wrapped around an external surface of a pipeline and can prevent a vandal or terrorist (e.g. in a conflict zone) from piercing the pipeline by firing a bullet or other projectile at the pipeline. Some pipelines are positioned above ground and are exposed to weather. In some examples, the apparatus 100 can include an external cover 1105 (see, e.g. Fig. 5) made from a suitable waterproof material. The cover can prevent ballistic resistant sheets 50 within the panel from being damaged by rain or other forms of precipitation. The cover can be UV- resistant and can prevent sun damage and any performance degradation associated therewith. In one example, the apparatus 100 can be installed after the pipeline is in place. The panels 100 can be attached to the pipeline using any suitable fasteners, including, for example, magnets, snaps, adhesives, or external straps. Two or more panels 100 can be interlocked using, for example, snaps, zippers, tongue and groove joints, or hook and look fasteners to prevent unwanted shifting of the panels after installation due to wind, which could leave portions of the pipeline exposed and vulnerable to ballistic threats.

[0046] The structural ballistic resistant apparatuses shown in Figs. 9, 10, 11 can be suitable replacements for traditional steel I-beams, round tubing, and box tubing, respectively. In some examples, an existing metal component (e.g. I-beam) can be replaced by a structural ballistic resistant apparatus 100 that contains no steel, such as the apparatus shown in Fig. 9. In other examples, a metal component 120 (e.g. round tubing or box tubing) can be part of a structural ballistic resistant apparatus 100 that is thinner, lighter, and less expensive than the component it replaces. The metal component 120 can serve as a structural metal liner for the structural ballistic apparatus 100. Through incorporation of the structural composite layer 505, the structural ballistic resistant apparatuses 100 shown in Figs. 9, 10, and 11 may have higher strength than the original metal components they replace. Moreover, the structural ballistic resistant apparatuses 100 shown in Figs. 9, 10, and 11 may have significantly higher strength-to-weight ratios than the original metal components they replace, which can be desirable when constructing buildings or when creating lightweight frames for automotive or aerospace applications. [0047] The structural ballistic resistant apparatuses 100 described herein can be incorporated into vehicle tires to protect the tires from ballistic threats. For example, a panel 100 can be incorporated into the sidewall of a military vehicle tire to prevent against punctures caused by projectiles. The panels 100 can replace heavy and costly steel armor. In one example, the panel 100 can be attached to a sidewall of the tire and can provide a protective covering that may be removable and replaceable if damaged. In another example, the panel can be integrated into the tire (e.g. disposed within the rubber compound of the tire). In this configuration, the panel 100 can protect the sidewall or the treaded surface of the tire from ballistic threats, including projectiles (e.g. bullets) or shrapnel from blasts caused by landmines or grenades.

[0048] The ballistic resistant apparatuses 100 described herein can be incorporated into temporary or permanent barricades. Barricades are often used to divert traffic and pedestrians at large public gatherings or to prevent vehicles from accessing certain areas. To protect citizens from certain terrorist threats at public gatherings (e.g. shrapnel from an improvised explosive device), it can be desirable to incorporate ballistic panels 100 described herein into a barricade. Due to their low weight and low cost, the panels 100 are well-suited for incorporation into a temporary barricade that is easily transported by one or more individuals and not significantly more expensive than a traditional temporary barricade.

Ballistic Performance Standards

[0049] The ballistic resistant apparatuses 100 described herein can be configured to comply with certain performance standards, such as those set forth in NIJ Standard- 0101.06, Ballistic Resistance of Body Armor (July 2008), which is hereby incorporated by reference in its entirety. The National Institute of Justice (NIJ), which is part of the U.S. Department of Justice (DO J), is responsible for setting minimum performance standards for law enforcement equipment, including minimum performance standards for police body armor. Under NIJ Standard-0101.06, personal body armor is classified into five categories (IIA, II, IIIA, III, IV) based on ballistic performance of the armor. Type IIA armor that is new and unworn is tested with 9 mm Full Metal Jacketed Round Nose (FMJ RN) bullets with a specified mass of 8.0 g (124 gr) and a velocity of 373 m/s ± 9.1 m/s (1225 ft/s ± 30 ft/s) and with .40 S&W Full Metal Jacketed (FMJ) bullets with a specified mass of 11.7 g (180 gr) and a velocity of 352 m/s ± 9.1 m/s (1155 ft/s ± 30 ft/s). Type II armor that is new and unworn is tested with 9 mm FMJ RN bullets with a specified mass of 8.0 g (124 gr) and a velocity of 398 m/s ± 9.1 m/s (1305 ft/s ± 30 ft/s) and with .357 Magnum Jacketed Soft Point (JSP) bullets with a specified mass of 10.2 g (158 gr) and a velocity of 436 m/s ± 9.1 m/s (1430 ft/s ± 30 ft/s). Type IIIA armor that is new and unworn is tested with .357 SIG FMJ Flat Nose (FN) bullets with a specified mass of 8.1 g (125 gr) and a velocity of 448 m/s ± 9.1 m/s (1470 ft/s ± 30 ft/s) and with .44 Magnum Semi Jacketed Hollow Point (SJHP) bullets with a specified mass of 15.6 g (240 gr) and a velocity of 436 m/s ± 9.1 m/s (1430 ft/s ± 30 ft/s).

[0050] Under the NIJ standard, Type III hard armor or plate inserts are tested in a conditioned state with 7.62 mm FMJ, steel jacketed bullets (U.S. Military designation M80) with a specified mass of 9.6 g (147gr) and a velocity of 847 m/s ± 9.1 m/s (2780 ft/s ± 30 ft/s). Type III flexible armor is tested in both the "as new" state and the conditioned state with 7.62 mm FMJ, steel jacketed bullets (U.S. Military designation M80) with a specified mass of 9.6 g (147 gr) and a velocity of 847 m/s ± 9.1 m s (2780 ft/s ± 30 ft/s). Type IV flexible armor is tested in both the "as new" state and the conditioned state with .30 caliber AP bullets (U.S. Military designation M2 AP) with a specified mass of 10.8 g (166 gr) and a velocity of 878 m/s ± 9.1 m/s (2880 ft/s ± 30 ft/s). For a Type III hard armor or plate insert that is tested as an "in conjunction" design with flexible armor, the flexible armor is tested in accordance with the NIJ standard as a standalone armor at a specified threat level. The combination of the flexible armor and hard armor/plate is then tested as a system and is found to provide protection at the system's specified threat level.

[0051] Under the NIJ standard, Type IV hard armor or plate inserts are tested in a conditioned state with .30 caliber armor piercing (AP) bullets (U.S. Military designation M2 AP) with a specified mass of 10.8 g (166 gr) and a velocity of 878 m/s ± 9.1 m/s (2880 ft/s ± 30 ft/s). Type IV flexible armor is tested in both the "as new" state and the conditioned state with .30 caliber AP bullets (U.S. Military designation M2 AP) with a specified mass of 10.8 g (166 gr) and a velocity of 878 m/s ± 9.1 m/s (2880 ft/s ± 30 ft/s). For a Type IV hard armor or plate insert that is tested as an "in conjunction" design with flexible armor, the flexible armor is tested in accordance with the NIJ standard and is found compliant as a stand-alone armor at its specified threat level. The combination of flexible armor and hard armor/plate is then tested as a system and is found to provide protection at the system's specified threat level.

[0052] The ballistic resistant apparatuses 100 described herein can be configured to comply with other performance standards, such as those set forth in the U.S. Department of Defense's Test Method Standard for Test Methods for Ballistic Defeat Materials (MIL-STD-3038, May 2011), which is hereby incorporated by reference in its entirety. The military standard covers test methods for ballistic defeat materials and solutions intended to provide protection against projectiles. The military standard provides types, classifications, and grades based on a ballistic protection limit (i.e. ballistic resistance). The classifications of ballistic resistant materials are based on the lethality of the projectile and cartridge used for testing. The classes of ballistic resistant materials are based on the material and design of the projectile used for testing.

[0053] The term "ballistic limit" describes the impact velocity required to perforate a target with a certain type of projectile. To determine the ballistic limit of a target, a series of experimental tests must be conducted. During the tests, the velocity of the certain type of projectile is increased until the target is perforated. The term "V50" designates the velocity at which half of the certain type of projectiles fired at the target will penetrate the target and half will not.

Methods of Manufacturing Structural Ballistic Resistant Apparatuses

[0054] Conventionally, a laminate is constructed by uniting two or more layers of material together. The process of creating a laminate conventionally refers to the placing an adherent material between layers of material and treating the stack of material to heat, pressure, or both.

[0055] One substantial problem with conventional methods of producing a laminate can be that the layers of laminatable material are open to the environment, which allows contaminants to associate with the laminate. Also, laminatable materials, if not properly sealed, can contaminate the environment. Another substantial problem with conventional methods of producing laminate can be that the adherent material, such as a resin, generates gas bubbles that can become entrapped between the layers of laminatable material during production. Another substantial problem with conventional methods can be that the amount of heat and pressure applied to the laminatable materials can be insufficient to produce laminates that resist penetration, such as by projectiles. Another substantial problem with conventional methods can be that the amount of heat and pressure applied to the laminatable materials can be insufficient to produce laminates that remain laminated for a desired amount of time, such as more than one year.

[0056] Generally referring to Figs. 12-24, and the description below, a lamination system including an apparatus and methods for producing a laminate 1, such as a structural ballistic resistant apparatus 100 made of a plurality of ballistic sheets 50, is shown and described. For the purposes of this method, the term "laminate" means a material constructed by uniting two or more layers of laminatable material 2 (where "laminatable material" can include ballistic resistant sheets 50, structural members (110, 115, 120, 125), carbon fiber fabric 1305 impregnated with resin, adhesive sheets, and waterproof covers 1105) together in accordance with one or more steps of the lamination method as shown in the figures and described below. The laminate 1 produced by the lamination method can take a wide variety of configurations from substantially planar forms (as shown by the example of Figs. 1A and 21) to three-dimensional forms (as shown by the example of Figs. 9, 10, 11, and 24) depending upon the application.

[0057] Now referring primarily to Fig. 12, the lamination method can include the step of obtaining or stacking at least two layers of laminatable material 2, such as two or more ballistic resistant sheets 50, which can be united by the application of sufficient amounts of heat and pressure by way of the methods described herein. Any number of layers of laminatable material 2 can be utilized with the method depending upon the application. The layers of laminatable material 2 can be in the form of sheets, such as ballistic-resistant sheets 50, which can be obtained as woven or non-woven materials, or the like. As examples, the layers of laminatable materials 2 can include sheets or material woven from ultra-high molecular weight polyethylene such as DYNEEMA or SPECTRA, aramid fibers such as KEVLAR, boron carbide, polypropylene such as INNEGRA available from Innegra Technologies, silicon carbide, alumina, alumina titanium, carbon, s-glass, e-glass, other materials described herein, or the like. The stack of layers 8 of laminatable material 2 can be bounded on one or more exterior surfaces by one or more structural members (e.g. 110, 115, 120, 125) as described herein and as shown in Figs. lA-11. In some examples, the structural members (e.g. 110, 115, 120, 125) can be structural composite layers 505 as described herein, and as shown in Figs. 1A-1C, 9-10, 21, and 24.

[0058] Each of the layers of laminatable material 2 can have a thickness 3 disposed between a first side 4 and a second side 5, as shown by the example in Fig. 2. The at least two layers of laminatable material 2 can be stacked to engage the first side 4 of a first layer of laminatable material 6 against the second side 5 of a second layer of laminatable material 7 and repeated until the number of layers of laminatable material 2 are sufficient for the particular application. The stacked layers of laminatable material 2, also referred to as a laminatable stack 8, have a top layer of laminatable material 9 and a bottom layer of laminatable material 10, as shown in Fig. 2.

[0059] An amount of adherent material 48 (more particularly as to certain embodiments, a resin) can be disposed between the layers of laminatable material 2 or applied to a surface of the layers of laminatable material. The amount of resin 48 can be provided as a separate material (e.g. sprayed, applied, or provided as a sheet) or the layers of laminatable material 2 can be pre-impregnated with the amount of resin 48 through an impregnation process during manufacturing of the laminatable material. The resin 48 can be any one or a combination of resins. Examples of resins 48 useful in bonding the layers of the laminatable material 2, include phenolic, epoxy, polyethylene terephthalate, vinylester, polyimides, bis(maleimide/diallybisphenol A, cyanate esters, thermoplastics, polypropylene, nylon, other resins identified herein, or the like.

[0060] As to certain embodiments, one or more layers of the laminate 1 produced as herein described or otherwise obtained can be located in the variable volume container 13 and treated by the apparatus and methods described herein.

[0061] In another step, the method can, but does not necessarily, further include engaging a first release layer 11 with the bottom layer of the structural ballistic resistant apparatus 100. The first release layer 11 can provide an interface that prevents contact between the bottom surface of the apparatus 100 and other the surfaces of other materials during subsequent steps in the lamination method. Certain embodiments may not include a first release layer 11 engaged with the bottom surface of the apparatus 100, as shown in the example of Fig. 12, or can include a first release layer 11 engaged with a second release layer 12 engaged with the first release layer 11, as shown in the example of Fig. 13. In other examples, any number of release layers can be utilized depending upon the embodiment or application.

[0062] In another step, embodiments of the method can further include engaging a first release layer 11 with the bottom surface of the apparatus 100, and the second release layer 12 with the top surface of the apparatus, as shown in Fig. 12. The second release layer 12 can provide an interface that prevents contact between the between the top layer of laminatable material 9, or laminate 1, and other the surfaces of other materials during subsequent steps in the lamination method. Certain embodiments of the method may not include a first release layer 11 or second release layer 12 correspondingly engaged with the top or bottom surfaces of the apparatus 100. In other examples, any number of release layers 11 can be utilized depending upon the embodiment or application. The composition of the second release layer 12 may be selected depending on the composition of the top surface of the apparatus 100 engaged by the second release layer 12. Because the top surface of the apparatus 100 can be different than the bottom surface of the apparatus, the first release layer 11 and the second release layer 12 can be, but are not necessarily, different in composition.

[0063] The term "release layer" includes any type of material that can be engaged to the bottom surface of the apparatus 100 or the top surface of the apparatus 100 during the lamination method for the production of the laminate 1 and can be subsequently removed from the laminate 1 without a substantial amount of the release layer 11, 12 remaining engaged with the apparatus upon completion of the method. The composition of the first release layer 11 can be selected depending on the composition of the bottom surface of the apparatus 100 engaged by the first release layer 11. As examples, the first release layer 11 (or second release layer 12, or a plurality of release layers) can include a fluorocarbon such as TEFLON, polytetrafluoroethylene coated fiberglass or silicon treated nylon 66, such as PEEL-PLY available from Airtech International, Inc., steel, aluminum, silicon, latex, rubber, or the like. [0064] In another step, the method can further include providing a variable volume container 13 having at least one flexible side wall 14, as shown in Figs. 12-15, 17, 19, 20, 22, and 23. The variable volume container 13 can, for example, take the constructional form of two superimposed sheets of flexible material 15,16 having superimposed edges 17, 18 that can at least in part be permanently sealed to provide as the remaining part of the superimposed edges 17, 18 a sealable or releasably sealable opening element 19. In some examples, the variable volume container 13 can be a vacuum bag. As shown by Fig. 12, as one example, the two superimposed sheets of flexible material 15, 16 can be permanently sealed along three superimposed edges 17, 18 (e.g. the bottom edge 20 and two side edges 21, 22) to provide the sealable opening element 19 that allows access to the inside of the variable volume container 13. As used herein, "permanently sealed" means that these edges are not intended to be opened during use of the variable volume container 13, and are not releasably sealable and are sufficiently sealed to allow retention of a vacuum pressure 23 within the variable volume container 13. The vacuum pressure 23 being lower pressure relative to atmospheric pressure 24, as further described below. Any method known to those of skill in the art, such as heat sealing, can be use to create the permanently sealed portion of the superimposed edges 17, 18 of the variable volume container 13. Variable volume containers 13 including more than two superimposed sheets of material 15, 16 can also be used to facilitate the method described herein. The variable volume container 13 can have a configuration that has any suitable shape, such as square or rectangular, as shown in the example of Figs. 12 and 13, and can operate between an open condition 25 shown in Fig. 12 and a closed condition 26 shown in Fig. 13. The variable volume container 13 can be produced from any material compatible with the pressure and temperature applied to the laminatable stack 8 to consolidate a laminate 1 to produce a structural ballistic resistant apparatus 100.

[0065] As to particular non-limiting embodiments of the method, the sealable opening element 19 can permit use of a pressure sensitive adhesive 27 coupled to the superimposed edge(s) 17, 18 that are not permanently sealed. The pressure sensitive adhesive 27 can be protected from inadvertent adherence. The phrase "protected from inadvertent adherence" means that the pressure sensitive adhesive 27 bearing superimposed edge 17 does not prematurely stick to a target surface 28 of the other superimposed edge 18 or to another portion of the superimposed sheets of flexible material 15, 16, or to any other surface, until activation of the pressure sensitive adhesive 27 by pressing the pressure sensitive adhesive 27 against the opposed target surface 29. Pressing the pressure sensitive adhesive 27 against the opposed target surface 29 results in a releasable seal generating the closed condition 26 of the variable volume container 13, as shown in Fig. 13.

[0066] In some embodiments of the method, the sealable opening element 19 can provide use of a groove element 29 matable with a groove-engaging element 30, as shown in Fig. 13. Pressing the groove-engaging element 30 into the groove element 29 can releasably seal to generate the closed condition 26 of the variable volume container 13. Any method known to those of skill in the art that allows the opening element 19 to be sealed either releasably such as with a pressure sensitive adhesive 27 or a groove- engaging element 30 into a groove element 29, or permanently such as heat-sealing, can be used to generate the closed condition 26 of the variable volume container 13. It is to be understood that the closed condition 13 of the variable volume container 13 can be generated by the use of any method of sealing that allows retention of a vacuum pressure 23 within the variable volume container 13 relative to atmospheric pressure 24, as further described below.

[0067] The method can include the step of inserting the laminatable stack 8 having a top surface and a bottom surface, correspondingly engaged to the first release layer 11 and the second release layer 12 inside of the variable volume container 13.

[0068] In another step, the method can include inserting at least one breather layer 31 between a) the at least one flexible wall 14 of the variable volume container 13 and the first release layer 11, b) between the at least one flexible wall 14 and the second release layer 12, or c) between the flexible wall 14 and both of the first release layer 11 and the second release layer 12. As to certain embodiments, the breather layer 31 can be used without a first release layer 11, or without the second release layer 12, or without either, depending on the type of breather layer 31 and the type layers of laminatable material 2 or adherent material 48. As used herein, the term "breather layer" means a layer of material sufficiently porous and of sufficient dimensional configuration to allow or assist in transfer of gases 32 within the variable volume container 13 in response to the vacuum pressure 23 applied to the variable volume container 13. The vacuum pressure 23, typically applied at the interface between the at least one flexible wall 14 and the breather layer 31 that is correspondingly engaged with the first release layer 11 or second release layer 12, each correspondingly engaged to the laminatable stack 8, as shown in the example of Fig. 12. Various types of breather layers 31 are described for example in U.S. Pat. Nos. 3,666,600; 4,062,917; 4,216,047; 4,353,855; and 4,548,859, each of which is hereby incorporated by reference in its entirety.

[0069] Now referring to Fig. 13, the method can further include a step of sealing the sealable opening element 19 to generate the closed condition 26 of the variable volume container 13. Again referring to Fig. 13, while certain embodiments of the method can be practiced without evacuating gases 32 from the variable volume container 13 (e.g. gases present inside of the variable volume container and at atmospheric pressure), the method can further include the step of evacuating gases 32 from inside the variable volume container 13. As used herein, the term "gases" means the gases held within the closed condition 32 of the variable volume container 13, which can include a mixture of gases, including atmospheric gases 33 trapped within the variable volume container 13 by achieving the closed condition 26 of the variable volume container 13 along with gases produced or released by the laminatable stack of ballistic sheets 8, the structural composite layer 505, the first release layer 11, the second release layer 12, the breather layer 31, the adherent material 48, the variable volume container 13, or otherwise, while at room temperature or at elevated temperatures as further described below, or due to achieving the vacuum pressure 23 inside of the variable volume container 13, as further described below. For the purposes of this method, the phrase "evacuating gases" means reducing pressure of the gas(es) 32 inside of the variable volume container 13 regardless of the process or equipment used to evacuate the gas(es). As shown in the non- limiting example of Fig. 13, the variable volume container 13 can include an evacuation element 34 through which an amount of the gas(es) 32 contained inside of the variable volume container 13 can flow from inside the variable volume container 13 to a location outside of the variable volume container 13. The evacuation element 34 can have a configuration that mates with a terminal fitting 35 of a vacuum conduit 36, as shown in the examples of Figs. 13-15. A vacuum generator 37 can generate a vacuum 38 within the vacuum conduit 36, which can be fluidly coupled with the gases 32 inside of the variable volume container 13 by engaging the terminal fitting 35 of the vacuum conduit 36 to the evacuation element 34 of the variable volume container 13. A vacuum pressure 23 within the variable volume container 13 can remove the gases 32 within the variable volume container 13. Regardless of the form of the vacuum source, the resulting vacuum pressure 23 in the variable volume container 13 can be less than atmospheric pressure in the range of about 750 Torr to about 10 Torr. Achieving a vacuum pressure 23 in the variable volume container 13 can be permit gases 32 contained in, or released by, layers of the structural ballistic resistant apparatus 100 to be evacuated from the variable volume container 13 prior to subsequent steps in the lamination method, especially upon heating the laminatable stack 8 and composite layer 505, as further described below. By releasing gases contained in the apparatus 100 relatively early in the lamination method, and by drawing those gases out of the variable volume container 13 by way of the vacuum conduit 36, laminates 1 with better ballistic performance and/or higher surface quality can be produced.

[0070] Again primarily referring to Fig. 13, in another step, the method can further include reducing the volume of the variable volume container 13 in response to the vacuum pressure 23 inside of the variable volume container 13. In the particular embodiment of the lamination method shown in Fig. 13, the two superimposed sheets of flexible material 17, 16, or at least one flexible wall 14, of the variable volume container 13 can be drawn against the apparatus 100 and associated first release layer 11 and second release layer 12 depending upon the embodiment, which can in part compressingly engage the layers of the apparatus together.

[0071] As to certain embodiments, the method can further include the step of sealing the evacuation element 34 to retain the vacuum pressure 23 inside of the variable volume container 13, and uncoupling the terminal fitting 35 of the vacuum conduit 36 from the evacuation element 34 of the variable volume container 13. Typically, however, the vacuum 38 will be continuously applied to maintain the vacuum pressure 23 inside of the variable volume container 13 to remove gases 32, including mixtures of gases generated by curing resins within the stack of ballistic sheets 8 and curing resins within the reinforcing fabric 1305 of the composite layer 505 during a heating step, as discussed below.

[0072] Now referring primarily to Fig. 14, the method can further include the step of heating the laminatable stack 8 outside of or within the variable volume container 13. As to certain embodiments, the stack of ballistic sheets 8 and a composite layer 505 made of a reinforcing fabric 1305 impregnated with a matrix material can be heated within the variable volume container 13. As to certain embodiments of the method, the heating step can be achieved during continuous evacuation of the variable volume container 13 to continuously maintain the vacuum pressure 23 inside of the variable volume container 13 at the vacuum pressure 23 described herein regardless of the mode of operation of the vacuum generator 37. The evacuated variable volume container 13 containing the stack of ballistic sheets 8 and the composite layer 505 can be sufficiently heated to allow consolidation of the stack of ballistic resistant sheets 8 and the composite layer 505, thereby producing a structural ballistic resistant apparatus 100. In some examples, as shown in Figs. 15-18, the consolidated assembly can be placed in a press mold and pressed to produce a three-dimensional apparatus 100 while the consolidated assembly is still at an elevated temperature and prior to solidifying and hardening of melted adhesives or resins within the assembly.

[0073] The term "consolidation" means sufficient adherence between the at least two layers of laminatable material 2 to allow production of a laminate 1. Typically, the at least two layers of laminatable material 2, once consolidated, will be substantially inseparable. The temperature 39 of the variable volume container 13 can be varied depending on a wide variety of lamination factors, such as, but not limited to: the composition, number, thickness, size, porosity, or other factors as to the at least two layers of laminatable material 2; or the vacuum pressure 23, atmospheric pressure 24, mold pressure, mold temperature, or other factors affecting the lamination process. The temperature 39 of the at least two layers of laminatable material 2, or the laminatable stack 8, can be in the range of about 10 degrees Celsius ("C.°") to about 400 C.° depending on the above described factors.

[0074] Regardless of the heat source, a wide variety of laminates 1 can be produced where the temperature is selected from the group including or consisting of: between about 10° C and about 50° C, between about 25° C and about 75° C, between about 50° C. and about 100° C, between about 75° C. and about 125° C, between about 100° C. and about 150° C, between about 125° C. and about 170° C, between about 150° C. and about 200° C, between about 175° C. and about 225° C, between about 200° C. and about 250° C, between about 225° C. and about 275° C, between about 250° C. and about 300° C, between about 275° C. and about 325° C, between about 300° C. and about 350° C, between about 325° C. and about 375° C, and between about 350° C. and about 400° C.

[0075] Again referring to Fig. 14, as to certain embodiments for the lamination method, heating of the evacuated variable volume container 13 and the laminatable stack 8 and composite layer 505 contained inside of the variable volume container 13 can be achieved by locating the evacuated variable volume container 13 inside of a heated enclosure 40, such as an oven, autoclave, or hydroclave, capable of maintaining a constant temperature 39 or generating a temperature gradient 41 (i.e. pre-selected change(s) in temperature 39 over a period of time that can be implemented automatically, such as by mechanical or computer implemented means, or manually) to heat the evacuated variable volume container 13, including the laminatable stack 8 or laminate 1, through a temperature gradient 41 or to a particular predetermined temperature 39.

[0076] Again referring primarily to Fig. 14, the method can further include the step of increasing pressure of the atmosphere gases 33 about the external surface of the evacuated variable volume container 13 while the laminatable stack 8, composite layer 505, one or more release layers 11,12 and breather layer 31 are within the variable volume container. As to certain embodiments of the lamination method, the step of increasing pressure of the atmosphere gases 33 about the external surface of the evacuated variable volume container 13 can be achieved during continuous evacuation of the variable volume container 13 to continuously maintain the vacuum pressure 23 inside of the variable volume container 13, regardless of the mode of operation of the vacuum generator 37. [0077] The evacuated variable volume container 13 containing the laminatable stack 8 and composite layer 505 can be sufficiently externally pressurized to urge the at least two layers of laminatable material 2 against one another to facilitate consolidation for production of the laminate 1 or to prepare the laminate 1 for press molding. The pressure of the atmospheric gases 33 in contact with the external surface of the variable volume container 13 can be varied depending on a wide variety of lamination factors, such as, but not limited to, the composition, number, thickness, size, porosity, or other factors as to the at least two layers of laminatable material 2; or the vacuum pressure 23, atmospheric pressure 24, mold pressure, mold temperature, or other factors affecting the lamination process. The pressure of the atmosphere gases 33 in contact with the external surface of the variable volume container 13 can be in the range of about 15 pounds per square inch ("psi") to about 50,000 psi depending on the above-described factors.

[0078] Again referring to Fig. 14, as to certain embodiments for the lamination method, the step of increasing pressure of the atmosphere gases 33 about the external surface of the evacuated variable volume container 13, and the step of heating of the evacuated variable volume container 13 and the laminatable stack 8 (or laminate 1) contained inside, can be achieved by locating the evacuated variable volume container 13 inside of a pressurized heated enclosure 42, such as an autoclave, capable of maintaining a constant external pressure 24 at a constant temperature 39 or generating a pressure gradient 42 or a temperature gradient 41 (pre-selected change(s) in the pressure or temperature, or both, over a period of time), which can be implemented automatically (by mechanical or computer implemented means) or manually to pressurize and heat the evacuated variable volume container 13, including the laminatable stack 8 and composite layer 505, according to either the pressure gradient 42, the temperature gradient 41, a particular atmospheric pressure 24, a particular temperature 39, or combination thereof.

[0079] Now referring to Figs. 15-18, in some examples, the lamination method can further include the step of placing the laminatable stack 8 (or laminate 1) in a press mold 43. The press mold 43 can have a first mold part 44 configured to be mated with a second mold part 45. The first mold part 44 and the second mold part 45 can take a numerous and wide variety of configurations. As one example, the matable portions of the first mold part 44 and the second mold part 45 can be substantially flat or planar as shown in the example of Figs. 15 and 16. As a second example, the first mold part 44 (e.g. female mold part) can be recessed or provide a receding or hollow part while the second mold part 45 (e.g. male mold part) can be correspondingly mateably raised as shown in the example of Figs. 17 and 18. While Fig. 17 shows a first mold part 44 that provides a recessed hemisphere and a second mold part 45 that provides a corresponding mateable raised hemisphere, the method is not so limited, and any manner of corresponding matable recessed and raised mold parts 44, 45 useful in producing a correspondingly configured laminate 1 can be utilized. Additionally, an advantage of the lamination method can be that the first mold part 44 and the second mold part 45 can be utilized at ambient temperature 46 and do not require heating prior to placing in the press mold 43 the variable volume container 13 having within it the heated evacuated laminatable stack 8 and composite layer 505 along with the associated release layers 11 12 and breather layer 31 for subsequent production of the laminate 1. However, this advantage is not intended to preclude embodiments of the method that use preheated press molds 43. [0080] To place the laminatable stack 8 (or laminate 1) in the press mold 43, the first mold part 44 and the second mold part 45 can be disposed a sufficient distance apart to allow the laminatable stack 8 to be placed between the first mold part 44 and the second mold part 45, as shown in Fig. 15 and 17. As to certain embodiments of the method, the laminatable stack 8 and composite layer 505 along with the associated first release layer 11, second release layer 12, and breather layer 31 can be place in the evacuated variable volume container 13, which can then be placed in the press mold 43. As to other embodiments of the method, the step of placing the laminatable stack 8 in the press mold 43 can be achieved during continuous evacuation of the variable volume container 13 to continuously maintain the vacuum pressure 23 inside of the variable volume container 13 at the vacuum pressure 23 described herein regardless of the mode of operation of the vacuum generator 37.

[0081] Now referring primarily to Figs. 16 and 18, the lamination method can further include the step of press molding the heated laminatable stack 8 (or one or more layers of laminate 1) contained within the evacuated variable volume container 13 between the first mold part 44 and the second mold part 45. Press molding can include moving the first mold part 44 and the second mold part 45 to exert sufficient mold pressure 47 on external surfaces of the evacuated variable volume container 13 containing the heated laminatable stack 8 and composite layer 505 to consolidate the at least two layers 2 to produce the structural ballistic resistant apparatus 100 (the laminate 1). The laminate 1 resulting from the press molding can remain contained within the evacuated variable volume container 13. The amount of mold pressure 47 transferred to the heated laminatable stack 8 (or heated one or more layers of laminate 1) within the evacuated variable volume container 13 can be sufficient to consolidate the at least two layers of laminatable material 2 over a period of time. When utilizing pre-consolidated laminate 1 prepared by the method described herein, or by any other method, there can be an advantage in applying heat and pressure to the laminate 1 in the variable volume container 13 evacuated to remove gases in that the laminate can further consolidate, maintain consolidation, or reduce loss of consolidation, which can maintain or increase advantageous properties of the laminate, such a tensile and/or compressive strength, ballistic performance, puncture resistance, resistance to delamination, or the like.

[0082] While the amount of mold pressure 47 utilized depends upon the lamination factors or the mold factors above described, the amount of mold pressure 47 exerted on the heated laminatable stack 8 within the evacuated variable volume container 13 to consolidate the at least two layers of laminatable material 2 (or mold the laminate 1) can be greater than 1,500 psi, or can be greater than 3,000 psi, or can be in the range of about 3,000 psi to about 10,000 psi. In particular, as to those embodiments of the which use a press mold 43 at ambient temperature, the mold pressure 47 transferred to the laminatable stack 8 (or the laminate 1) can be sufficient to consolidate the heated laminatable stack 8 (or mold the laminate 1 without loss of the advantageous properties described herein) within the evacuated variable volume container 13, which can occur in a wide range of between about 15 psi and about 50,000 psi. In regard to certain methods, increased resistance of the laminate 1 to penetration or stab can be achieved with increased pressure of between about 75 psi and about 250 psi. Certain embodiment of the method can be performed at between 1,500 psi and about 50,000 psi. The period of time in which the amount of pressure is applied to the laminatable stack 8 can be as little as about one second, and there is no upper limit as to the amount of time that can be used to consolidate the laminatable stack 8.

[0083] A pressure source can apply pressure to the laminatable stack 8 and composite layer 505 by way of vacuum pressure within the variable volume container 13, by way of external pressure of atmospheric gases 33 in contact with the external surface of the variable volume container 13, by way of a press or press mold 43, or a combination thereof. The pressure applied by the pressure source can be selected from one or more of the pressures included in or selected from the group consisting of: between about 15 pounds per square inch and about 75 pounds per square inch, between about 50 pounds per square inch and about 150 pounds per square inch, between about 75 pounds per square inch and about 250 pounds per square inch, between about 200 pounds per square inch and about 1000 pounds per square inch, between about 500 pounds per square inch and about 1,500 pounds per square inch, between about 1,000 pounds per square inch and about 3,000 pounds per square inch, between about 2,000 pounds per square inch and about 4,000 pounds per square inch, between about 3,000 pounds per square inch and about 5,000 pounds per square inch, between about 4,000 pounds per square inch and about 6,000 pounds per square inch, between about 5,000 pounds per square inch and about 7,000 pounds per square inch, between about 6,000 pounds per square inch and about 8,000 pounds per square inch, between about 7,000 pounds per square inch and about 9000 pounds per square inch, between about 8,000 pounds per square inch and about 10,000 pounds per square inch, between about 9,000 pounds per square inch and about 20,000 pounds per square inch, between about 15,000 pounds per square inch and about 25,000 pounds per square inch, between about 20,000 pounds per square inch and about 30,000 pounds per square inch, between about 25,000 pounds per square inch and about 35,000 pounds per square inch, between about 30,000 pounds per square inch and about 40,000 pounds per square inch, between about 35,000 pounds per square inch and about 45,000 pounds per square inch, and between and about 40,000 pounds per square inch and about 50,000 pounds per square inch.

[0084] Now referring primarily to Figs. 19 and 22, the lamination method can further include the step of removing a laminate 1 contained within the evacuated variable volume container 13 from the press mold 43. Removal of the laminate 1 contained within the evacuated variable volume container 13 can be achieved by separating the first mold part 44 from the second mold part 45 to allow release of the laminate 1 contained within the evacuated variable volume container 13 from the first mold part 44 or the second mold part 45 of the press mold 43. Certain embodiments of the method can further include the step of cooling the laminate 1 contained within the evacuated variable volume container 13 for a period of time prior to removal from the press mold 43 such period of time sufficient to retain the configuration of the laminate 1 outside of the press mold 43. The lamination method can further include the step of disengaging the breather layer 31 from the first release layer 11 and disengaging the first release layer 11 and the second release layer 12 from the opposed sides of the laminate 1.

[0085] Now referring to Figs. 20 and 23, the lamination method can further include the step of removing the laminate 1 (structural ballistic resistant apparatus 100) from the variable volume container 13. Removal of the laminate 1 can include the step of releasing the vacuum pressure 23 within the variable volume container 13. Release of the vacuum pressure 23 within the variable volume container 13 can be achieved as to certain embodiments of the method for disengaging the terminal fitting 35 of the vacuum conduit 36 from the evacuation element 34 to allow ingress of atmospheric gases 33 into the variable volume container 13. As to other embodiments of the method, the release of vacuum pressure 23 can be achieved by generating the open condition 25 of the variable volume container 13 by opening the sealable opening element 19. The laminate 1, along with the associated first release layer 11, second release layer 12, and breather layer 31, can be removed from the variable volume container 13.

[0086] Now referring primarily to Figs. 21 and 24, the method can further include the step of producing a laminate 1 (e.g. a structural ballistic resistant apparatus 100) by use of the lamination method. The laminate 1 can include the consolidation of the at least two layers of laminatable material 2 (e.g. at least two layers of ballistic resistant sheets with a composite cover 505) by stepwise application of any of the embodiments of the lamination method above described.

Ballistic Resistant Sheet Construction

[0087] A structural ballistic resistant apparatus 100 (e.g. panel, column, beam, wall, member, or any other type of structure) can be made of one or more ballistic resistant sheets 50, as shown in Fig. IB. The term "sheet," as used herein, can describe one or more layers containing any suitable material, such as a polymer, metal, fiberglass, ceramic, composite, or combination thereof. Examples of polymers include aramids, para-aramids, meta-aramids, polyolefms, and thermoplastic poly ethylenes. Commercially-available examples of aramids, para-aramids, meta-aramids are sold under the trademarks NOMEX, KERMEL, KEVLAR, TWARON, NEW STAR, TECHNORA, HERACRON, and TEIJINCONEX. An example of a polyolefm is sold under the trademark INNEGRA. Examples of thermoplastic polyethylenes include TENSYLON from E. I. du Pont de Nemours and Company, DYNEEMA from Dutch-based DSM, and SPECTRA from Honeywell International, Inc., which are all ultra-high-molecular-weight polyethylenes (UHMWPE). Examples of glass fibers include A-glass (soda lime silicate glass), C-glass (e.g. calcium borosilicate glass), D-glass (e.g. borosilicate glass), E-glass (e.g. alumina-calcium-borosilicate glass), E-CR-glass (calcium aluminosilicate glass), R- glass (e.g. calcium aluminosilicate glass), S-glass, S-2 glass (e.g. magnesium aluminosilicate glass fibers ranging from about 5 to 24 μιη), and T-glass. Other suitable fibers include M5 (polyhydroquinone-diimidazopyridine), which has high strength and is fire-resistant.

[0088] The ballistic resistant sheets 50 can be constructed using any suitable manufacturing process, such as extruding, die cutting, forming, pressing, weaving, rolling, etc. In certain instances, the ballistic resistant sheets 50 can be manufactured accordingly to a proprietary or trade secreted method. The ballistic resistant sheets 50 can include a woven or non-woven construction consisting of a plurality of fibers bonded by a resin, such as a thermoplastic polymer, thermoset polymer, elastic resin, or other suitable resin.

[0089] The ballistic resistant sheets 50 can be pre-impregnated with a resin, such as thermoplastic polymer, thermoset polymer, epoxy, or other suitable resin. The resin can be partially cured to allow for easy handling and storage of the ballistic resistant sheet prior to formation of the structural ballistic resistant apparatus 100. To prevent complete curing (e.g. polymerization) of the resin before the sheet 50 is incorporated into a apparatus 100, the ballistic resistant sheet may require cold storage. In other examples, the ballistic resistant sheets 50 may or may not be pre-impregnated, and a sheet of film adhesive may be inserted between two adjacent ballistic resistant sheets to promote bonding of the adjacent ballistic resistant sheets by melting the film adhesive via a heating process. Suitable film adhesives are available from Collano AG, located in Germany.

[0090] In another example, the ballistic resistant sheets 50 can be made of ultra- high-molecular-weight polyethylene (UHMWPE) and can be formed by any suitable process, such as one of the processes described in U.S. Patent Nos. 7,923,094 to Harding et al, 7,470,459 to Weedon et al, or 7,348,053 to Weedon et al, which are hereby incorporated by reference in their entirety. The resulting ballistic resistant sheets 50 can have ballistic properties that distinguish them from sheets made of aramid fibers.

Commercially Available Ballistic Resistant Sheets

[0001] Ballistic resistant sheets 50 constructed from high performance fibers, such as fibers made of aramids, para-aramids, meta-aramids, polyolefms, or ultra-high- molecular-weight polyethylenes, are commercially available from a variety of manufacturers. Several specific examples of commercially available ballistic resistant sheets 50 made of high performance fibers are provided below. Ballistic resistant sheets 50 are commercially available in many configurations, including uni-ply, 0/90 x-ply, and 0/90/0/90 double x-ply configurations. Ballistic resistant sheeting material 50 can be ordered in a wide variety of forms, including tapes, laminates, rolls, sheets, structural sandwich panels, and preformed inserts, which can all be cut to size during a manufacturing process. [0002] TechFiber, LLC, located in Arizona, manufactures a variety of ballistic resistant sheets 50 made of aramid fibers that are sold under the trademark K-FLEX. One version of K-FLEX is made with KEVLAR fibers having a denier of about 1000 and a pick count of about 18 picks per inch. K-FLEX can have a resin content of about 15- 20%. Different versions of K-FLEX may contain different resins. For instance, a first version of K-FLEX can include a resin (e.g. a polyethylene resin) with a melting temperature of about 215-240 degrees F, a second version of K-FLEX can include a resin with a melting temperature of about 240-265 degrees F, a third version of K-FLEX can include a resin with a melting temperature of about 265-295 degrees F, and a fourth version of K-FLEX can include a resin with a melting temperature of about 295-340. K- FLEX is available in uni-ply, 0/90 x-ply, and 0/90/0/90 double x-ply configurations.

[0003] TechFiber, LLC also manufactures a variety of unidirectional ballistic resistant sheets 50 made of aramid fibers that are sold under the trademark T-FLEX. Certain versions of T-FLEX can have a resin content of about 15-20% and can include aramid fibers such as TWARON fibers (e.g. model number T765). Different versions of T-FLEX may contain different resins. For instance, a first version of T-FLEX can include a resin (e.g. a polyethylene resin) with a melting temperature of about 215-240 degrees F, a second version of T-FLEX can include a resin with a melting temperature of about 240-265 degrees F, a third version of T-FLEX can include a resin with a melting temperature of about 265-295 degrees F, and a fourth version of T-FLEX can include a resin with a melting temperature of about 295-340 degrees F. T-FLEX is available in uni-ply, 0/90 x-ply, and 0/90/0/90 double x-ply configurations. [0004] Polystrand, Inc., located in Colorado, manufactures a variety of unidirectional ballistic resistant sheets 50 made of aramid fibers that are sold under the trademark THERMOBALLISTIC. One version of THERMOBALLISTIC ballistic resistant sheets are sold as product number TBA-8510 and include aramid fibers with a pick count of about 12.5 picks per inch. Other versions of THERMOBALLISTIC ballistic resistant sheets are sold as product numbers TBA-8510X and TBA-9010X and include aramid fibers (e.g. KEVLAR fibers) and have a 0/90 x-ply configuration. The resin content of the THEMROBALLISTIC ballistic resistant sheets can be about 10-20% or 15-20%. Different versions of THERMOBALLISTIC ballistic resistant sheets may contain different resins. For instance, a first version of THERMOBALLISTIC ballistic resistant sheets can include a resin with a melting temperature of about 225-255 degrees F, a second version of THERMOBALLISTIC ballistic resistant sheets can include a resin (e.g. a polypropylene resin) with a melting temperature of about 255-295 degrees F, a third version of THERMOBALLISTIC ballistic resistant sheets can include a resin (e.g. a polypropylene resin) with a melting temperature of about 295-330 degrees F, a fourth version of THERMOBALLISTIC ballistic resistant sheets can include a resin with a melting temperature of about 330-355 degrees F, and a fifth version of THERMOBALLISTIC ballistic resistant sheets can include a resin with a melting temperature of about 355-375 degrees F. One version of THERMOBALLISTIC ballistic resistant sheets can include a polypropylene resin. THERMOBALLISTIC ballistic resistant sheets are available in uni-ply, 0/90 x-ply, and 0/90/0/90 double x-ply configurations. [0005] E. I. du Pont de Nemours and Company (DuPont), located in Delaware, manufactures a ballistic resistant sheet material 50 made of ultra-high-molecular- weight polyethylene fabric that is sold under the trademark TENSYLON. A Material Data Safety Sheet was prepared on February 2, 2010 for a material sold under the tradename TENSYLON HTBD-09-A (Gen 2) by BAE Systems TENSYLON High Performance Materials. The Material Safety Data Sheet is identified as TENSYLON MSDS Number 1005, is publicly available, and is hereby incorporated by reference in its entirety. The ballistic resistant sheets are marketed as being lightweight and cost-effective and boast low back face deformation, excellent flexural modulus, and superior multi-threat capability over other commercially available ballistic resistant sheets. The ballistic resistant sheet material can be purchased on a roll and can be cut into ballistic resistant sheets 50 having a size and shape dictated by an intended application.

[0006] Honeywell International, Inc., headquartered in New Jersey, manufactures a variety of ballistic resistant sheets 50 made of aramid fibers that are sold under the trademarks GOLD SHIELD and GOLD FLEX. One version of GOLD SHIELD ballistic resistant sheets 50 are sold under product number GN-2117 and are available in 0/90 x- ply configurations and have an areal density of about 3.2 ounces per square yard.

[0007] Barrday, Inc., headquartered in Cambridge, Ontario, manufactures a variety of ballistic resistant sheets 50 made of para-aramid fibers that are sold under the trademark BAR FLEX. One version of BARRFLEX ballistic resistant sheets 50 is sold as product number U480 and is available in 0/90 x-ply configurations. Each layer of the ballistic resistant sheet 50 is individually constructed with a thermoplastic film laminated to a top and bottom surface. [0008] Teijin Limited, headquartered in the Netherlands, manufactures a ballistic resistant sheet material 50 made of ultra-high-molecular-weight polyethylene fabric in a solvent-free process. The sheet material 50 is sold under the trademark ENDUMAX and is available with a thickness of about 55 micrometers.

Structural Apparatus Constructed from UHMWPE Ballistic Resistant Sheets

[0091] In some examples, the structural ballistic resistant apparatus 100 can include a stack of ballistic resistant sheets 8 made of UHMWPE fabric. The ballistic resistant sheets 50 can be arranged according to a two-dimensional shape to form a three- dimensional stack of ballistic resistant sheets. In some examples, the two-dimensional shape can coincide with the perimeter of a vehicle body panel. In other examples, the two-dimensional shape can coincide with the shape of a structural member, such as a middle portion an I-beam, as shown in Fig. 9. The number of ballistic resistant sheets 50 incorporated in the stack 8 can vary depending on an anticipated threat level. In some examples, the number of ballistic resistant sheets 50 can be about 10-20, 20-100, 100- 180, 180-220, 220-260, at least 100, or at least 260. Where even greater ballistic performance is required, the number of ballistic resistant sheets 50 can be increased to about 260-500, 500-1,000, or 1,000-1,200. The number of ballistic resistant sheets 50 can depend on the thickness of the UHMWPE ballistic resistant sheet material. If the thickness of each ballistic resistant sheet is increased, the overall number of ballistic resistant sheets can be reduced. Regardless of the thickness of each ballistic resistant sheet or the overall number of ballistic resistant sheets, the stack of ballistic resistant sheets can have a thickness of about 0.125-0.5, 0.25-1.5, or 1.0-2.5 to ensure versatility and low weight. However, where even greater ballistic performance is required, the thickness of the stack of ballistic resistant sheets 8 can be increased to about 2.0-4.5, 4.0- 6.0, 5.0-8.0, or 7.5-10 inches.

[0092] In one example, the ballistic resistant sheets 50 can be arranged in a homogeneous stack, where all ballistic resistant sheets in the stack 8 are made from the same type of UHMWPE ballistic resistant sheet material, such as TENSYLON or ENDUMAX ballistic resistant sheet material. In other examples, any of the other suitable types of ballistic resistant sheets (e.g. sheets made of aramid or glass fibers, sheets made of ceramic, or sheets made of metal) can be interspersed in the stack of UHMWPE ballistic resistant sheet material to alter the ballistic performance of the stack. In another example, a sheet of film adhesive 48, such as sheet of film adhesive available from Collano, can be interspersed in the stack of ballistic resistant sheets 8 to alter the ballistic performance of the stack. In particular, a sheet of adhesive film can be incorporated within the stack near a strike face side of the stack to improve stab resistance of the stack. A sheet of adhesive film can be incorporated within the stack 8 near a wear face side of the stack to improve back face deformation of the stack.

[0093] The stack of ballistic resistant sheets 8 can be heated to form a laminated stack of ballistic resistant sheets. The heat can be provided by, for example, an infrared oven, autoclave, hydroclave, conventional oven, or any other suitable heat source. In one example, the ballistic resistant sheets 50 can include UHMWPE, and the ballistic resistant sheets 50 can be coated with a resin layer made of a thermoplastic polymer. The resin layer can have a melting point in the range of about 215-245, 240-260, or 250-275 degrees F. The resin layer can be uniformly or non-uniformly distributed onto each ballistic resistant sheet 50. In one example, the resin layer can be spattered onto the ballistic resistant sheets 50. In another example, the resin layer can be applied in a uniform layer to the ballistic resistant sheets 50. In yet another example, the resin layer can be an adhesive film applied to the ballistic resistant sheets 50. During the heating process, the temperature of the stack of ballistic resistant sheets 8 can be increased to about 215-245, 240-260, or 250-275 degrees Fahrenheit to promote softening or melting of the resin layer on the ballistic resistant sheets 50.

[0094] During heating of the stack of ballistic resistant sheets 8, the outer portions of the stack may increase in temperature before the inner portions of the stack. To ensure adequate heating of the resin layers on the inner portions of the ballistic resistant sheets in the stack 8, the heating step may have a duration of at least 5 minutes. The duration may depend on the number of sheets 50 in the stack and the chemical composition of the resin layers on each ballistic resistant sheet. In certain examples, the duration may be about 15-30, 30-45, 45-60, 60-120, 120-240, or 240-480 minutes. The proper duration can be determined through experimentation (e.g. by implanting a thermocouple within a sample stack and monitoring its temperature during a heating process) or by employing a computational heat transfer program to quantify heat transfer rates and determine when the center of the stack (and the resin in that area) will reach a target temperature. It can be desirable to increase the temperature of all portions of the stack of ballistic resistant sheets 8 to a temperature at, near, or above the melting or softening point of the resin layer on each ballistic resistant sheet to achieve lamination of the ballistic resistant sheets in the stack.

[0095] Where lamination of certain layers is not desired, such as near the middle of the stack 8, the heating process can be halted before the resin near the middle of the stack reaches its melting or softening point. In some examples, superior ballistic performance has been observed when at least a portion of the ballistic resistant sheets 50 within the stack are not fully laminated or are only partially laminated.

Vacuum Bagging

[0096] Prior to the heating process, the stack of ballistic resistant sheets 8 and the structural composite layer 505 can be placed in a variable volume container 13, such as a vacuum bag, and gas that is present between adjacent ballistic resistant sheets 50 can be evacuated from the variable volume container, thereby compressing the stack of ballistic resistant sheets 8 and reducing its thickness. This is known as a vacuum bagging process. During the vacuum bagging process, the stack of ballistic resistant sheets 8 can be inserted into a vacuum bag, and the bag can be sealed with, for example, vacuum bag sealant tape. A vacuum hose 36 of a vacuum pump 37 can then be connected to a vacuum port 35 on the vacuum bag 13, and the pump can be operated to evacuate air from the vacuum bag. A breather layer 31 can be positioned between the stack of ballistic resistant sheets 8 and an inner surface of the vacuum bag 14 to permit uniform evacuation of gas from the vacuum bag. The breather layer 31 can be made of an air- permeable material that provides a gas pathway to encourage uniform evacuation of air from within the vacuum bag. As gas is evacuated from the vacuum bag 13, the air pressure inside the bag decreases. Meanwhile, the ambient air pressure acting on the outside of the vacuum bag 13 remains at atmospheric pressure (e.g. -14.7 psi). The pressure differential between the air pressure inside and outside the vacuum bag is sufficient to produce a compressive force acting against the stack of ballistic resistant sheets 8. The compressive force is applied uniformly over the stack of ballistic resistant sheets 8, which can produce a panel with uniform or nearly uniform thickness.

[0097] Despite the relatively modest pressure differential established between the ambient air pressure outside of the vacuum bag 13 and the reduced air pressure inside the bag, the vacuum bagging process can produce a stack of ballistic resistant sheets that is thinner than the stack was prior to the vacuum bagging process. In many applications, reducing the thickness of the stack, even if only by a small percentage (e.g. about 1- 10%), is highly desirable. For instance, if the stack must fit within a slot that is about 2 inches wide in a military vehicle door or floor panel, by vacuum bagging the stack 8, the thickness of the stack can be reduced, which allows additional ballistic resistant sheets to be incorporated into the stack, which can significantly improve the ballistic performance of the stack. In certain applications, such as in ballistic resistant panels in military vehicles (e.g. tanks or mine-resistant ambush protected (MRAP) vehicles), improving the ballistic performance of the panel incrementally can be a life-saving improvement.

[0098] In one example, the vacuum bag 13 can be made of a transparent polymer material and can be sized to accommodate one structural ballistic resistant apparatus 100. In another example, the vacuum bag 13 can be sized to accommodate a plurality of apparatuses 100. For instance, the vacuum bag 13 can be sized to accommodate 2 or more, 2-20, 4-12, or 6-10 ballistic apparatuses 100. Vacuum bagging batches of ballistic panels can be more efficient that vacuum bagging single panels. Also, vacuum bagging batches of panels allows for quality testing of at least one panel per batch. Quality testing of a panel may involve destructive testing, such as firing projectiles at the panel to determine a V50 rating or a ballistic protection level. Therefore, it is desirable to make two or more panels in an identical vacuum bagging process, where it can be assumed that one or more panels that are not destructively tested will perform similarly to the panel that has been destructively tested and must be discarded.

[0099] The vacuum bag 13 used in the vacuum bagging process can be a reusable vacuum bag, which can reduce consumables and decrease labor costs. The reusable vacuum bag 13 can be made from any suitable material, such as LEXAN, silicone rubber, TEFLON, fiberglass reinforced polyurethane, fiberglass reinforced polyester, or KEVLAR reinforced rubber.

Structural Member

[00100] Many ballistic resistant apparatuses 100 provide suitable ballistic protection but are incapable of serving as structural members, since they are too weak to withstand significant compressive forces along multiple axes (e.g. x, y and z axes), since ballistic resistant sheets typically have poor compressive strength. When developing vehicles and dwellings that are resistant to ballistic threats, it can be desirable to incorporate one or more ballistic resistant apparatuses 100 that also serve as structural supports. Ballistic resistant apparatuses 100 that incorporate one or more structural support members can significantly reduce the weight of a vehicle, which can reduce the vehicle's fuel consumption and can improve the vehicle's range.

[00101] It can be desirable to produce a ballistic resistant apparatus 100 that incorporates one or more structural members (e.g. 110, 115, 120, 125, 505), as shown in Figs. lA-11. The structural members can be made out of any suitable material or materials that increase the load-bearing capabilities of the ballistic resistant panel (e.g. when the panel is exposed to compressive or tensile forces). The material used to form the one or more structural members of the apparatus 100 can vary depending on the intended application of the apparatus. For instance, where the purpose of the structural member (e.g. 110, 115, 120, 125, 505) is to bolster the stiffness of the ballistic resistant apparatus 100 and improve the apparatus' ability to withstand torsional or tensile forces without experiencing deflection or elongation, the structural member may be made of a carbon fiber composite material or a fiberglass composite material (e.g. a composite material containing S-glass fibers). In another example, where the purpose of the structural member is to bolster the stiffness of the ballistic resistant panel 100 and enhance ballistic performance of the panel, the structural member may be made of a metal or ceramic material. Suitable metals that can enhance the ballistic performance of the panel include, for example, aluminum, steel, titanium, and magnesium. Suitable ceramics that can enhance the ballistic performance of the panel include silicon carbide, boron carbide, zirconia toughened alumina, and high-density aluminum oxide. Suitable ceramic materials that can enhance ballistic performance are commercially available from CoorsTek, Inc., located in Golden, Colorado and are sold under the trademarks CERASHIELD and CERCOM. Other suitable ceramic materials are commercially available from CeramTec GmbH, located in Germany.

[00102] The structural member (e.g. 110, 115, 120, 125, 505) can be adapted to serve as a load-bearing member. As a load-bearing member, the structural member may effectively serve as a support structures that is capable of bearing weight placed on the ballistic resistant panel and effectively transferring that load to other structural elements that are connected to the structural member (e.g. to a foundation of a building or to a chassis of a vehicle). [00103] Prior to placing the stack of ballistic sheets 8 into the variable volume container 13, a composite material can be placed on one or more outer surfaces of the stack. In one example, the composite material can entirely encase the stack, as shown in Fig. 1A-1C. In another example, the composite material may be placed on a top surface and a bottom surface of the stack 8, as shown in Fig. 2. In yet another example, the composite material can be placed on a top surface, bottom surface, or end surface of the stack. Through the vacuum bagging process, the composite material can be transformed from a reinforcing fabric 1305 impregnated with a matrix material (e.g. resin) into a structural member that is adapted to serve as a load-bearing member. For instance, the structural member can be adapted to endure compressive or tensile forces without significant deflection, elongation, or compression. In addition, the structural member can effectively protect the edges of the stack of ballistic sheets 8 from becoming damaged during, for example, transport, installation, or use. It is desirable to protect the edges of the stack of ballistic sheets 50, since damage to an edge of the stack can decrease ballistic performance. For instance, if the edge of the stack is exposed to a compressive force (e.g. if the stack being dropped or bumped), the sheets in the stack may delaminate near the edge of the stack, thereby reducing the ballistic performance of the panel in that region.

[00104] The structural member (e.g. 110, 115, 120, 125, 505) can be made of any suitable composite material such as, for example, carbon fiber composite, or fiberglass composite material. A composite material containing carbon fiber and epoxy is an example of an excellent structural material due to the stiffness of carbon fiber and the high tensile strength and extremely low elongation exhibited by carbon fiber. The structural member can be formed by any suitable process, such as a wet layup process (e.g. hand layup or resin infusion) where liquid resin (e.g. amorphous thermoplastic such as epoxy) is distributed over a woven or nonwoven fabric made of carbon or glass fibers to wet out the fabric. The wet layup process can utilize a release layer 11 (e.g. peel ply layer) or mold release agent to prevent the structural composite layer 505 from adhering to the inner surface of the variable volume container 13.

[00105] The structural composite layer 505 or layers can take on any suitable form depending on the intended application of the ballistic resistant apparatus 100. In one example, as shown in Fig. 1, the structural ballistic resistant apparatus 100 can include a structural composite layer 505 that includes a first structural member 110 adjacent to a top side of a stack of ballistic resistant sheets 8 and a second structural member 115 adjacent to a bottom side of the stack of ballistic resistant sheets 8. The first and second structural members (110, 115) can bound the stack of laminated ballistic resistant sheets 8 around a perimeter of the stack and can be adapted to be load-bearing members. The first and second structural members (110, 115) can be made of composite material such as, for example, carbon fiber composite material or fiberglass composite material that is infused, coated, or impregnated with a matrix material.

[00106] As load-bearing members, the first and second structural members (110, 115) can effectively serve as support structures to bear a load placed on the structural ballistic resistant apparatus 100 and can effectively transfer that load to other structural elements that are connected to the first and second structural members (e.g. a foundation of a building or a chassis of a vehicle). In one example, the laminated stack of ballistic resistant sheets 8 can bear a portion of the load. In another example, the laminated stack of ballistic resistant sheets 8 may be isolated from the load and may not bear any portion of the load, leaving the structural composite layer 505 to bear the entire load.

[00107] In one example shown in Fig. 2, the first structural member 110 and the second structural member 115 can fully encase the stack of ballistic resistant sheets 8. As shown in Fig. 2, the first and second structural members (110, 115) can be joined around a perimeter of the stack of ballistic resistant sheets 8 to fully encase the stack of ballistic resistant sheets. By bonding the first structural member 110 to the second structural member 115, the load-bearing capabilities of the panel 100 can be significantly increased. Encasing the stack of ballistic resistant sheets 8 may also protect the stack from damage caused by liquids or chemicals.

[00108] As shown in Figs. 3-8, the structural ballistic resistant apparatus 100 can include a third structural member 120. The third structural member 120 can be made of any suitable metal or ceramic material. Suitable metals that can be included in the third structural member 120 and that can enhance the ballistic performance of the panel 100 include aluminum, steel, titanium, and magnesium. Suitable ceramics that can be included in the third structural member 120 and that can enhance the ballistic performance of the panel 100 include silicon carbide, boron carbide, zirconia toughened alumina, high-density aluminum oxide.

[00109] As shown in Figs. 3, 4, and 8, the structural ballistic resistant apparatus 100 can include a fourth structural member 125. The fourth structural member 125 can be made of any suitable metal or ceramic material. Suitable metals that can be included in the fourth structural member 125 and that can enhance the ballistic performance of the panel 100 include aluminum, steel, titanium, and magnesium. Suitable ceramics that can be included in the fourth structural member 125 and that can enhance the ballistic performance of the panel 100 include silicon carbide, boron carbide, zirconia toughened alumina, high-density aluminum oxide.

[00110] As shown in Figs. 6, 7, and 8 the first structural member 110 and the second structural member 115 can encase the stack of ballistic resistant sheets 8, the third structural member 120, and, if present, the fourth structural member 125. When struck by a projectile, the third and fourth structural members (120, 125), which can be made of metal or ceramic, may produce fragments. To prevent fragments from traveling beyond the back surface of the panel 100, the panel can be fully encased by the first and second structural members (110, 115), which can be made of a composite material. In this way, the first and second structural members (110, 115), along with the stack of ballistic resistant sheets 8, may serve as spall liners to capture metal or ceramic fragments produced by the third and fourth structural members (120, 125), thereby reducing the likelihood of damage or injury caused by fragments.

[00111] The structural ballistic resistant apparatus 100 can be formed into any suitable load-bearing shape. For example, the structural ballistic resistant apparatus 100 can be formed into a structural beam, such as an I-beam. Fig. 9 shows a cross-sectional view of a structural ballistic resistant apparatus 100 formed into an I-beam. The apparatus 100 can include a laminated stack of ballistic resistant sheets 205. In the example shown in Fig. 9, the stack of ballistic resistant sheets 8 can be arranged in a horizontal stack. In another example, the stack of ballistic resistant sheets can be arranged in a vertical stack. In another example, the stack of ballistic resistant sheets can be arranged in a stack in a direction aligned with the length of the I-beam. The I-beam can be formed by a top structural member 210, a bottom structural member 215, a left side structural member 220, and a right side structural member 225. The left and right side structural members (220, 225) can each have a C-shape as shown in Fig. 9. The left side structural member 220 can join the top structural member 210 to the bottom structural member 215. Likewise, the right side structural member 225 can join the top structural member 210 to the bottom structural member 215.

Structural Composite Layer

[00112] The structural member (110, 115, 120, 125) of the ballistic resistant apparatus 100 can be a structural composite layer 505 made from a reinforcing material 1305 combined with a matrix material, such as a resin. In some examples, the reinforcing material 1305 can be made from a plurality of fibers arranged into a woven or nonwoven fabric. To produce the fabric, an individual fiber, known as a filament or strand, can be combined with other fibers to form a bundle, known as a tow. A plurality of tows can then be combined to form a woven or nonwoven fabric. The reinforcing material 1305 can be a fabric that is constructed from graphite fibers (commonly referred to as "carbon fibers"), glass fibers, KEVLAR fibers, carbon nanotubes, or any other suitable high- performance fibers. In some examples, the reinforcing fabric 1305 can be a hybrid of two or more types of high-performance fibers, such as a hybrid fabric made of carbon fibers and KEVLAR fibers. The fabric can be constructed as a woven, knitted, stitched, or nonwoven (e.g. uni-directional) fabric. Examples of suitable woven fabrics include Style 7725 Bi-directional E-Glass (Item No. 1094), Twill Weave Carbon Fiber Fabric (Item No. 1069), and KEVLAR Plain Weave Fabric (Item No. 2469), all available from Fibre Glast Developments Corporation of Brookville, Ohio. [00113] In some examples, the matrix material can be a thermoset resin, such as polyester, vinyl ester, epoxy, phenolic, polyurethane, silicone, polyamide, or polyamide- imide. Of the thermoset resins listed above, polyester, vinyl ester, and epoxy are the most common thermosetting resins. Thermoset resins offer high thermal stability, high rigidity and hardness, and suitable resistance to creep. Thermosetting resins are relatively easy to work with, because at room temperature (and prior to curing), they remain in a liquid state, which allows them to be distributed over a reinforcing material with relative ease. A thermoset resin in a liquid state can be conveniently applied to a reinforcing fabric made of, for instance, fiberglass, carbon fiber, or KEVLAR fibers. In other examples, the matrix material can be a thermoplastic resin.

[00114] The woven or nonwoven fabric 1305 can be coated or impregnated with matrix material. In some examples, the woven or nonwoven fabric 1305 can be pre- impregnated with matrix material and maintained in cold storage to prevent the matrix material from curing (if permitted to cure, the fabric would harden and become unworkable, which is undesirable prior to the vacuum bagging step). The matrix material can be selected based on properties of the reinforcing material 1305 and the desired attributes of the structural ballistic resistant apparatus 100. Once the matrix material has been selected, the parameters of a suitable manufacturing process can be selected to adequately cure the resin. Depending on the characteristics of the selected matrix material and reinforcing material, an oven or autoclave may be employed to speed the process of fully curing (i.e. polymerizing) the matrix material to effectively reduce manufacturing cycle times. A variety of suitable temperatures and durations are described herein for fully curing the matrix material using, for example, an oven or autoclave to produce a finished structural ballistic resistant apparatus 100 with a high- quality surface finish and exceptional ballistic performance.

[00115] In some instances, the matrix material can be applied to the reinforcing material 1305 during a lamination process, either by hand or through an infusion process. In other instances, the manufacturer of the reinforcing material may introduce matrix material to the reinforcing material to create a pre-impregnated reinforcing material, which is commonly referred to as a "prepreg fabric." Prepreg fabrics typically require cold storage to ensure the resin does not cure prematurely. Prepreg fabrics can be more convenient to work with than non-prepreg fabrics, since a relatively messy wet layup process can be avoided, but prepreg fabrics can also be more costly to purchase and store due to the expense associated with impregnating the reinforcing material with matrix material prior to shipping and the need for temperature-controlled storage before, during, and after shipping.

[00116] As noted above, the matrix material can be a thermosetting resin, such as an epoxy resin, vinyl-ester resin, or polyester resin. Resin selection can be based, at least in part, on fabric 1305 compatibility and the intended application and characteristics of the ballistic resistant apparatus 100. In many instances, epoxy resins are desirable for use in composites, since they produce strong and light composite parts that are dimensionally stable. An example of a suitable epoxy resin is System 2000 Epoxy Resin (Item No. 2000-A) available from Fibre Glast Developments Corporation.

[00117] The System 2000 Epoxy Resin can be mixed with a suitable epoxy hardener, such as 2020 Epoxy Hardener (Item No. 2020-A), 2060 Epoxy Hardener (Item No. 2060-A), or 2120 Epoxy Hardener (Item No. 2120-A) from Fibre Glast Developments Corporation. Selection of an epoxy hardener can be based, at least in part, on desired pot life and working time, which may be dictated by the size and complexity of the structural ballistic resistant apparatus 100 being produced. For instance, where the apparatus 100 is larger or more complex, a craftsman may need a longer working time to ensure necessary fabrication steps can be completed before the resin cures. Epoxy hardener selection can also be based on desired cure temperature and cure time. A variety of suitable manufacturing temperatures and times are described herein for manufacturing the ballistic resistant apparatus 100. An epoxy hardener should be selected that is compatible with the chosen manufacturing temperature and time. The post-cured service temperature of the ballistic resistant apparatus 100 should also be considered when selecting an epoxy hardener. Specifically, the craftsman should consider where the apparatus will be used and what temperatures will be encountered in that environment. Certain epoxy hardeners, such as 2120 Epoxy Hardener, have service temperatures of over 200 degrees Fahrenheit, which can be desirable for high temperature applications, such as for ballistic resistant apparatuses that will be incorporated into firewalls or engine shrouds of vehicles.

[00118] A structural composite layer 505 containing a combination of carbon fiber fabric 1305 and epoxy is an example of an excellent structural component (e.g. 110) due to its high tensile strength, high compressive strength, high flexural strength, and excellent heat resistance and machinability. The structural composite layer 505 can be formed over the stack of ballistic sheets 8 in any suitable process, such as a wet layup process where liquid resin is distributed over a fabric made of carbon or glass fibers to wet out the fabric. The liquid resin can be distributed by hand, by a resin infusion process, or by any other suitable process. The wet layup process can utilize a release layer 11 or mold release agent to prevent the composite structural layer 505 from adhering to a vacuum bag 13 during a vacuum bagging process. An example of a suitable release layer is Peel Ply Release Fabric (Catalog No. VB-P56150) available from U.S. Composites, Inc. of West Palm Beach, Florida.

[00119] During a layup process, the stack of ballistic sheets 8 can be laid on top of a sheet of reinforcing fabric 1305 that has been trimmed to an appropriate size. One or more additional sheets of reinforcing fabric 1305 can then be wrapped around the stack of ballistic sheets 8 to encase the stack of ballistic sheets, as shown in Figs. 1A-1C. Resin can then be applied to the surface of the reinforcing fabric (1305, 1405) using any suitable tool, such as a roller or brush. Through a vacuum bagging process, the resin will be forced into the fabric 1305 to adequately wet out the fabric with resin. When prepreg reinforcing fabric 1305 is used in the layup, the step of applying resin can be omitted, since the fabric already contains a suitable amount of resin to facilitate the lamination process. Regardless of whether prepreg or non-prepreg fabrics are used, it may be necessary to use a release layer 11 between the reinforcing fabric 1305 and the inner surface of the vacuum bag 13 to prevent the composite layer from adhering to the vacuum bag as the resin cures during the vacuum bagging process. Using a release layer 11 (peel ply layer) can result in a higher quality surface finish on the composite layer 505 and can also protect the flexible wall 14 of the vacuum bag 13 from being damaged during the vacuum bagging process. Accordingly, if undamaged, the vacuum bag can be reused. In other examples, where the quality of the composite layer's 505 surface finish is unimportant (e.g. where the composite layer 505 will not be visible in the final product, such as when covered with a waterproof cover 1105), the release layer 11 can be omitted.

[00120] To encourage the composite layer 505 to adhere or laminate to the stack of ballistic sheets 8, it may be necessary to insert a layer of resin or film adhesive between the composite layer 505 and the stack of ballistic resistant sheets 8. The resin or film adhesive can be an epoxy, epoxy foam, liquid resin, or any other suitable film adhesive. Examples of suitable film adhesives are available from Collano. The resin or film adhesive layer may be activated by applying heat and pressure, and upon cooling, will effectively bond the structural composite layer 505 to the stack of ballistic resistant sheets 8. The resin or film adhesive layer can be used between any two adjacent surfaces in the structural ballistic resistant apparatus 100 (the laminate 1) to improve bonding between the adjacent surfaces.

[00121] In some examples, the stack of ballistic sheets 8 can be wrapped with one or more sheets of reinforcing fabrics 1305 to form a composite layer 505, as shown in Fig. IB. In some examples, the reinforcing fabric 1305 can be placed adjacent to the outer surfaces of the stack of ballistic sheets 8 and joined to form a perimeter joint around a perimeter region of the stack of ballistic resistant sheets, as shown in Fig. IB, through the method described herein. In other examples, the reinforcing fabrics 1305 can be wrapped around the stack of ballistic sheets 8 similar to the way a gift box is wrapped with wrapping paper. For instance, a sheet of reinforcing material 1305 can be laid on a flat surface. The stack of ballistic resistant sheets 8 can then be placed on top of the sheet of reinforcing material 1305, and the edges of the sheet of reinforcing material can then be folded up and over the respective edges of the stack of ballistic resistant sheets 8, similar to the way a gift is wrapped with wrapping paper, to produce a wrapped stack of ballistic resistant sheets 50. At this point, if needed, resin can be applied to the exterior of the first sheet of reinforcing material 1305. The wrapped stack of ballistic resistant sheets 8 can then be processed according to the process parameters described herein to produce a finished structural ballistic resistant apparatus 100.

[00122] In another example, instead of processing the wrapped stack of ballistic sheets 8 after the first sheet of reinforcing material 1305 has been applied, a second sheet of reinforcing material can be applied over the first sheet of reinforcing material prior to processing. During application of the second sheet of reinforcing material 1405, the wrapped stack of ballistic sheets 8 can first be placed on top of the second sheet of reinforcing material 1405, and the edges of the second sheet of reinforcing material can then be folded up and over the respective edges of the wrapped stack of ballistic sheets 8, similar to the way a gift is wrapped with wrapping paper, to produce a twice-wrapped stack of ballistic sheets 8. In some examples, it may be desirable to flip the stack of ballistic sheets 8 over between application of the first and second sheets of reinforcing material. For instance, if the front surface of the stack was placed downward against the first sheet of reinforcing material 1305, it may be desirable to flip the stack over so that the rear surface of the stack is facing downward against the second sheet of reinforcing material 1405. At this point, if needed, resin can be applied to the exterior of the second sheet of reinforcing material 1405. The wrapped stack can then be processed according to the process parameters described herein to produce a finished ballistic resistant apparatus 100 (e.g. a process including vacuum bagging and heating). [00123] Additional layers of reinforcing material (e.g. three or more layers) can be added to the stack of ballistic sheets 8 prior to processing to further enhance the structural properties of the structural composite layer 505 of the structural ballistic resistant apparatus 100.

Waterproof Cover

[00124] The structural ballistic resistant apparatus 100 can be encased in a protective cover 1105, as shown in Fig. 5. In some examples, the cover 1105 can be a waterproof cover, thereby producing a waterproof structural ballistic resistant apparatus 100. The cover 1105 can be adapted to prevent the ingress of liquid through the cover toward the ballistic resistant sheets 50 encased by the cover. Preventing water ingress can be desirable, since moisture can negatively affect the performance of the ballistic resistant sheets 50. In particular, moisture can negatively affect tensile strength of certain fibers (e.g. aramid fibers) within the ballistic resistant sheets 50, thereby resulting in the sheets being less effective at dissipating impact energy from a projectile.

[00125] The cover 1105 can be made from any suitable material such as, for example, rubber, NYLON, RAYON, ripstop NYLON, carbon fiber, fiberglass, CORDURA, polyvinyl chloride (PVC), polyurethane, silicone elastomer, fluoropolymer, or any combination thereof. The cover 1105 can be a coating that contains polyurethane, polyuria, or epoxy, such as a coating sold by Rhino Linings Corporation, located in San Diego, California. In another example, the cover can be made from any suitable material and coated with a waterproof material such as, for example, rubber, PVC, polyurethane, polytetrafluoroethylene, silicone elastomer, fluoropolymer, wax, or any combination thereof. In one example, the cover can be made from NYLON coated with PVC. In another example, the cover 1105 can be made from NYLON coated with thermoplastic polyurethane. The cover 1105 can be made of any suitable material, such as about 50, 70, 200, 400, 600, 840, 1050, or 1680-denier NYLON coated with thermoplastic polyurethane. In yet another example, the cover can be made from 1000-denier CORDURA coated with thermoplastic polyurethane.

[00126] In addition to protecting the ballistic resistant sheets from water ingress, the cover 1105 can be made of a chemically-resistant material to protect the ballistic resistant sheets if the panel is exposed to acids or bases. Certain acids and bases can cause the tenacity of certain fibers, such as aramid fibers, to degrade over time, where "tenacity" is a measure of strength of a fiber or yarn. It is therefore desirable, in certain applications, for the cover 1105 to be resistant to acids and bases to prevent the cover from deteriorating when exposed to acids or bases. Deterioration of the cover 1105 would be undesirable, since it would permit the acids and bases to breach the cover material and reach the stack of ballistic resistant sheets inside the cover. To this end, the cover 1105 can be made of a chemically resistant material or can include a chemically resistant coating on an outer surface of the cover. For instance, the cover 1105 can include a thermoplastic polymer coating on an outer surface of the cover. Examples of chemically-resistant thermoplastic polymers that can be used to coat the cover 1105 include polypropylene, low-density polyethylene, medium-density polyethylene, high- density polyethylene, ultra-high-molecular-weight polyethylene, and polytetrafluoroethylene (e.g. TEFLON).

[00127] The cover 1105 can made of a flame-resistant or flame-retardant material. In one example, the cover 1105 can include a flame-resistant or flame-retardant material mixed with a base material. In another example, the cover 1105 can include a base material coated with a flame-resistant or flame-retardant material. In yet another example, the cover 1105 can include a base material with a flame -resistant or flame- retardant material chemically bonded to the base material. The flame -resistant or flame- retardant material can be a phenolic resin, a phenolic/epoxy composite, NOMEX, an organohalogen compound (e.g. chlorendic acid derivative, chlorinated paraffin, decabromodiphenyl ether, decabromodiphenyl ethane, brominated polystyrene, brominated carbonate oligomer, brominated epoxy oligomer, tetrabromophthalic anyhydride, tetrabromobisphenol A, or hexabromocyclododecane), an organophosphor^ous compound (e.g. triphenyl phosphate, resorcinol bis(diphenylphosphate), bisphenol A diphenyl phosphate, tricresyl phosphate, dimethyl methylphosphonate, aluminum diethyl phosphinate, brominated tris, chlorinated tris, or tetrekis(2- chlorethyl)dichloroisopentyldiphosphate, antimony trioxide, or sodium antimonite), or a mineral (e.g. aluminium hydroxide, magnesium hydroxide, huntite, hydromagnesite, red phosphorus, or zinc borate).

[00128] The cover 1105, along with the stack 8 of ballistic resistant sheets, can be heated and subjected to a vacuum bagging process, thereby partially or fully bonding an inner surface of the cover 1105 to the outer surface of the structural composite layer 505, as shown in Fig. 5. The cover 1105 can include a temperature sensitive adhesive or a layer of resin on an inner surface. The cover 1105 can be heated to promote full or partial bonding of the inner surface of the cover to the stack of ballistic resistant sheets 8 due to melting or softening of the adhesive or resin. In one example, the cover can be made of a material that is coated with polyurethane, polypropylene, vinyl, polyethylene, or a combination thereof, on the inner surface the cover. Heating the cover to a temperature above the melting point of the adhesive or resin and then cooling the cover below the melting point of the adhesive or resin can result in bonding of the inner surface of the cover to the stack of ballistic resistant sheets.

[00129] In some examples, the cover 1105 can be made of ripstop NYLON and coated with polyurethane. The cover 1105 can be made of ripstop NYLON with a polyurethane coating that is about 0.1-1.5, 0.1-0.75, 0.1-0.5, or 0.25 mil thick. The cover 1105 can be made of 70-denier ripstop NYLON with a polyurethane coating that is about 0.1-1.5, 0.1-0.75, 0.1-0.5, or 0.25 mil thick. The polyurethane coating can be provided on an inner surface of the cover 1105. A durable water repellant finish can be provided on an outer surface of the cover 1105. Suitable polyurethane coated ripstop NYLON materials are commercially available under the trademark X-PAC from Rockywoods Fabrics, LLC located in Loveland, Colorado.

Ballistic Resistant Sheet Resin

[00130] Ballistic resistant sheets 50 can be coated or impregnated with one or more resins. Certain resins, such as resins made of thermoplastic polymers, may include long chain molecules. The chains of molecules may be held close to each other by weak secondary forces. Upon heating, the secondary forces may be reduced, thereby permitting sliding of the chains of molecules and resulting in visco-plastic flow and ease in molding. Heating of the ballistic resistant sheets 50 may cause softening of the resin, and the resin may become tacky as it softens. Applying pressure to the panel when the resin is softened and tacky may result in resin layers on adjacent ballistic resistant sheets becoming comingled, and when the panel is subsequently cooled and the temperature of the resin is reduced, adjacent ballistic resistant sheets may be partially or fully bonded (e.g. laminated) to each other. In one example, ballistic resistant sheets 50 in a stack 8 may be coated or impregnated with a thermoplastic (e.g. polypropylene) resin, and the thermoplastic resin may have a melting point of about 248 degrees F. The stack of ballistic resistant sheets 8 may be heated to a temperature near 248 degrees F to cause softening of the thermoplastic resin, and pressure may be applied to the stack to press adjacent ballistic resistant sheets together, which may result in comingling of resin layers on adjacent sheets. When the panel 100 can is cooled and the temperature of the resin is reduced, adjacent ballistic resistant sheets 50 may be partially or fully bonded to each other, resulting in a laminated stack of ballistic resistant sheets 8.

[00131] When forming a ballistic resistant apparatus 100 from one or more ballistic resistant sheets 50 containing one or more resins, a suitable processing temperature for the apparatus can be dictated, at least partly, by the resin type and resin content (i.e. percent weight) of the ballistic resistant sheets 50. Selecting a resin with a lower melting point may reduce the target processing temperature for the apparatus, and selecting a resin with a higher melting point may increase the target processing temperature for the apparatus. The extent of lamination (e.g. full or partial bonding) that occurs between adjacent ballistic resistant sheets 50 in the stack 8 can be controlled, at least in part, by resin selection, resin content, and process temperature and pressure. Heating Process

[00132] During formation of the structural ballistic resistant apparatus 100, the stack of ballistic resistant sheets can be heated in a heating process. Heating can promote bonding (e.g. partial or full) between adjacent ballistic resistant sheets. Full or partial bonding is desirable since it can enhance the panel's ability to dissipate impact energy of a projectile that strikes the panel 100 as the ballistic resistant sheets 50 within the panel experience delamination. During delamination, adjacent ballistic resistant sheets that were partially or fully bonded (e.g. laminated) prior to impact are separated (i.e. delaminated) in response to the projectile entering the panel, and the energy required to separate those ballistic resistant sheets 50 is extracted from the projectile, thereby reducing the speed of the projectile and eventually stopping the projectile. A panel 100 containing ballistic resistant sheets that are laminated together by a heating process can more effectively dissipate impact energy from a projectile than a panel that has no bonding and is simply a stack of ballistic resistant sheets sewn together or held loosely by a cover or encasement.

[00133] In one example, heating of the stack 8 of ballistic resistant sheets 50 can occur while the stack is being vacuum bagged (i.e. while the stack 8 is still sealed within the vacuum bag 13). Applying a vacuum while heating the laminatable materials 2 is preferable, since gases produced by resins curing within the stack of ballistic sheets 8 and the composite layer 505 can be drawn away from the laminate 1 to ensure that gas bubbles are not trapped within the laminate, which can provide better ballistic performance and a higher quality surface finish. In other examples, the stack of laminatable materials 2 can be heated after vacuum bagging and after the laminate 1 has been removed from the vacuum bag. In yet another example, heating can occur before the laminatable materials 2 have been subjected to a vacuum bagging process. Heating can occur using any suitable heating equipment such as, for example, a conventional oven, infrared oven, hydroclave, or autoclave. During the heating process, a process temperature can be selected based, at least in part, on a melting point of one or more resins that are incorporated into one or more of the ballistic resistant sheets 50 in the stack. For instance, if the stack 8 includes a ballistic resistant sheet 50 containing a thermoplastic polymer resin with a melting temperature at about 248 degrees F, the process temperature can be increased to about 220, 215-240, 230-245, or about 240-260 degrees F to promote softening or melting of the resin in the ballistic resistant sheets 50 to produce a laminated stack of ballistic resistant sheets.

[00134] The UHMWPE found in some ballistic sheet material can have a melting point of about 266-277 degrees Fahrenheit. In some instances, it can be desirable to maintain a heating temperature below the melting point of the UHMWPE material to avoid altering the ballistic properties of the material. In other instances, it can be desirable for the heating temperature to exceed the melting temperature to promote melting of the UHMWPE material to intentionally alter the ballistic properties of the UHMWPE.

[00135] To promote partial or full bonding (e.g. lamination) of adjacent ballistic resistant sheets 50 in the stack 8, the stack can be heated to a suitable temperature for a suitable duration. Suitable temperatures and durations depend on the type of resin present in the one or more UHMWPE ballistic resistant sheets in the stack 8 and the type of resin in the composite layer 505. Examples of suitable process temperatures and durations for a heating process for any of the various stacks of ballistic resistant sheets described herein can include, for example: 125-550 degrees F for at least 1 second; 125- 550 degrees F for at least 5 minutes; 125-550 degrees F for at least 15 minutes; 125-550 degrees F for at least 30 minutes; 125-550 degrees F for at least 60 minutes; 125-550 degrees F for at least 90 minutes; 125-550 degrees F for at least 120 minutes; 125-550 degrees F for at least 180 minutes; 125-550 degrees F for at least 240 minutes; 125-550 degrees F for at least 480 minutes; 225-350 degrees F for at least 1 second; 225-350 degrees F for at least 5 minutes; 225-350 degrees F for at least 15 minutes; 225-350 degrees F for at least 30 minutes; 225-350 degrees F for at least 60 minutes; 225-350 degrees F for at least 90 minutes; 225-350 degrees F for at least 120 minutes; 225-350 degrees F for at least 180 minutes; 225-350 degrees F for at least 240 minutes; 250-350 degrees F for at least 1 second; 250-350 degrees F for at least 5 minutes; 250-350 degrees F for at least 15 minutes; 250-350 degrees F for at least 30 minutes; 250-350 degrees F for at least 60 minutes; 250-350 degrees F for at least 90 minutes; 250-350 degrees F for at least 120 minutes; 250-350 degrees F for at least 180 minutes; 250-350 degrees F for at least 240 minutes; 250-300 degrees F for at least 1 second; 250-300 degrees F for at least 5 minutes; 250-300 degrees F for at least 15 minutes; 250-350 degrees F for at least 30 minutes; 250-300 degrees F for at least 60 minutes; 250-350 degrees F for at least 90 minutes; 250-300 degrees F for at least 120 minutes; 250-300 degrees F for at least 180 minutes; 250-300 degrees F for at least 240 minutes; 225-275 degrees F for at least 1 second; 225-275 degrees F for at least 5 minutes; 225-275 degrees F for at least 15 minutes; 225-275 degrees F for at least 30 minutes; 225-275 degrees F for at least 60 minutes; 225-275 degrees F for at least 90 minutes; 225-275 degrees F for at least 120 minutes; 225-275 degrees F for at least 180 minutes; 225-275 degrees F for at least 240 minutes; 225-250 degrees F for at least 1 second; 225-250 degrees F for at least 5 minutes; 225-250 degrees F for at least 15 minutes; 225-250 degrees F for at least 30 minutes; 225-250 degrees F for at least 60 minutes; 225-250 degrees F for at least 90 minutes; 225-250 degrees F for at least 120 minutes; 225-250 degrees F for at least 180 minutes; 225-250 degrees F for at least 240 minutes; 240-260 degrees F for at least 1 second; 240-260 degrees F for at least 5 minutes; 240-260 degrees F for at least 15 minutes; 240-260 degrees F for at least 30 minutes; 240-260 degrees F for at least 60 minutes; 240-260 degrees F for at least 90 minutes; 240-260 degrees F for at least 120 minutes; 240-260 degrees F for at least 180 minutes; 240-260 degrees F for at least 240 minutes; 140-225 degrees F for at least 1 second; 140-225 degrees F for at least 5 minutes; 140-225 degrees F for at least 15 minutes; 140-225 degrees F for at least 30 minutes; 140-225 degrees F for at least 60 minutes; 140-225 degrees F for at least 90 minutes; 140-225 degrees F for at least 120 minutes; 140-225 degrees F for at least 180 minutes; or 140-225 degrees F for at least 240 minutes. For any of the above-mentioned process temperatures and durations for a heating process, the stack of UHMWPE ballistic resistant sheets 8 may be sealed within a vacuum bag during the heating process. In certain examples, a vacuum hose 36 extending from a vacuum pump 37 can remain connected to a vacuum port 35 on the vacuum bag 13 during the heating process, as shown in Fig. 14. This configuration can ensure good results even if the vacuum bag 13 is not perfectly sealed.

[00136] Exposing the apparatus 100 to higher temperatures during the heating process can effectively reduce cycle times, which is desirable for mass production. Due to the thickness of the apparatus 100 and heat transfer properties of the apparatus, exposing the apparatus to a high temperature (e.g. 550 degrees F) for a relatively short duration may allow the inner portion of the panel to achieve a target temperature needed for bonding (e.g. 240-275 degrees F) more quickly than if the heat source was initially set to the target temperature needed for bonding. When high temperatures are employed, it can be desirable to fill the heated enclosure 40 with an inert gas, such as nitrogen, to reduce the risk of a combustion event within the heated enclosure.

Applying, Pressure

[00137] During formation of the structural ballistic resistant apparatus 100, pressure can be applied to the stack of ballistic resistant sheets 8. Pressure can promote partial or full bonding (e.g. lamination) of adjacent ballistic resistant sheets 50 in the stack 8 to form a laminated stack of ballistic resistant sheets. Pressure can be applied to the stack of ballistic resistant sheets 8 using a mechanical press, autoclave, hydroclave, bladder press, or other suitable device. In one example, pressure can be applied to the stack during the heating process, as shown in Fig. 14, using gas pressure. In another example, pressure can be applied to the stack of ballistic resistant sheets 8 before the heating process. In yet another example, pressure can be applied to the stack of ballistic resistant sheets after the heating process, as shown in Figs. 16 and 18. In still another example, pressure may not be applied to the stack of ballistic resistant sheets 8 aside from the relatively modest pressure applied through the vacuum bagging process shown in Fig. 13. If pressure is applied to the stack of ballistic resistant sheets 8, it can occur after the stack of ballistic resistant sheets has been vacuum bagged and while the stack is still in the vacuum bag 13 and being heated, as shown in Fig. 14. Alternately, pressure can be applied to the stack of ballistic resistant sheets 8 after the stack has been removed from the vacuum bag or before the stack is inserted into the vacuum bag 13.

[00138] During a process involving both heat and pressure (e.g. using a pressurized heated enclosure 42 as shown in Fig. 14), a process temperature can be selected based on a melting point of resin (e.g. a layer of resin on one side of each ballistic resistant sheet 50) present on the one or more of the ballistic resistant sheets in the stack 8. For instance, if the stack 8 includes a ballistic resistant sheet 50 containing a first resin with a melting temperature near 250 degrees F, the process temperature can be increased to about 220-240, 235-245, or 230-255 degrees F to promote softening or melting of the first resin in the ballistic resistant sheet 50.

[00139] To promote lamination (e.g. partial or full bonding) of adjacent ballistic resistant sheets in the stack 8, a suitable pressure can be applied to the stack for a suitable duration or, where appropriate, momentarily. Suitable pressures and durations may depend on the type of resin present in the one or more ballistic resistant sheets 50 in the stack 8. Examples of suitable process pressures and durations for any of the various stacks of ballistic resistant sheets 50 described herein can include, for example: 10-100 psi for at least 1 second, 10-100 psi for at least 1 minute; 10-100 psi for at least 5 minutes; 10-100 psi for at least 15 minutes; 10-100 psi for at least 30 minutes; 10-100 psi for at least 60 minutes; 10-100 psi for at least 90 minutes; 10-100 psi for at least 120 minutes; 10-100 psi for at least 180 minutes; 10-100 psi for at least 240 minutes; 50-75 psi for at least 1 second; 50-75 psi for at least 5 minutes; 50-75 psi for at least 15 minutes; 50-75 psi for at least 30 minutes; 50-75 psi for at least 60 minutes; 50-75 psi for at least 90 minutes; 50-75 psi for at least 120 minutes; 50-75 psi for at least 180 minutes; 50-75 psi for at least 240 minutes; 50-100 psi for at least 1 second; 50-100 psi for at least 5 minutes; 50-100 psi for at least 15 minutes; 50-100 psi for at least 30 minutes; 50-100 psi for at least 60 minutes; 50-100 psi for at least 90 minutes; 50-100 psi for at least 120 minutes; 50-100 psi for at least 180 minutes; 50-100 psi for at least 240 minutes; at least 10 psi for at least 1 second; at least 10 psi for at least 5 minutes; at least 10 psi for at least 15 minutes; at least 10 psi for at least 30 minutes; at least 10 psi for at least 60 minutes; at least 10 psi for at least 90 minutes; at least 100 psi for at least 120 minutes; at least 10 psi for at least 180 minutes; at least 10 psi for at least 240 minutes; at least 100 psi for at least 1 second; at least 100 psi for at least 5 minutes; at least 100 psi for at least 15 minutes; at least 100 psi for at least 30 minutes; at least 100 psi for at least 60 minutes; at least 100 psi for at least 90 minutes; at least 100 psi for at least 120 minutes; at least 100 psi for at least 180 minutes; or at least 100 psi for at least 240 minutes.

[00140] Lower pressures may be achievable with, for example, a manual press or a small autoclave. In other examples, higher pressures can be applied to the stack of ballistic resistant sheets with, for example, an industrial autoclave, hydroclave, bladder press (e.g. made of KEVLAR reinforced rubber), a pneumatic press, or a hydraulic press. To promote lamination (e.g. partial or full bonding) of adjacent ballistic resistant sheets in the stack 8, a suitable pressure can be applied to the stack 8 for a suitable duration or momentarily. Suitable pressures and durations may depend on the types of resin present in the one or more ballistic resistant sheets in the stack. Examples of suitable process pressures and durations for any of the various stacks of ballistic resistant sheets 8 described herein can include, for example: at least 500 psi for at least 1 second; at least 500 psi for at least 5 minutes; at least 500 psi for at least 15 minutes; at least 500 psi for at least 30 minutes; at least 500 psi for at least 60 minutes; at least 500 psi for at least 90 minutes; at least 500 psi for at least 120 minutes; at least 500 psi for at least 180 minutes; at least 500 psi for at least 240 minutes; at least 1,000 psi for at least 1 second; at least 1,000 psi for at least 5 minutes; at least 1,000 psi for at least 15 minutes; at least 1,000 psi for at least 30 minutes; at least 1,000 psi for at least 60 minutes; at least 1,000 psi for at least 90 minutes; at least 1,000 psi for at least 120 minutes; at least 1,000 psi for at least 180 minutes; or at least 1,000 psi for at least 240 minutes; at least 2,500 psi for at least 1 second; at least 2,500 psi for at least 5 minutes; at least 2,500 psi for at least 15 minutes; at least 2,500 psi for at least 30 minutes; at least 2,500 psi for at least 60 minutes; at least 2,500 psi for at least 90 minutes; at least 2,500 psi for at least 120 minutes; at least 2,500 psi for at least 180 minutes; or at least 2,500 psi for at least 240 minutes.

[00141] Examples of other suitable process pressures and durations for any of the various stacks of ballistic resistant sheets 8 described herein can include, for example: 40- 90 psi for at least 1 second; 40-90 psi for at least 1 minute; 40-90 psi for at least 5 minutes; 40-90 psi for at least 15 minutes; 40-90 psi for at least 30 minutes; 40-90 psi for at least 60 minutes; 40-90 psi for at least 90 minutes; 40-90 psi for at least 120 minutes; 40-90 psi for at least 180 minutes; 40-90 psi for at least 240 minutes; 60-90 psi for at least 1 second; 60-90 psi for at least 1 minute; 60-90 psi for at least 5 minutes; 60-90 psi for at least 15 minutes; 60-90 psi for at least 30 minutes; 60-90 psi for at least 60 minutes; 60-90 psi for at least 90 minutes; 60-90 psi for at least 120 minutes; 60-90 psi for at least 180 minutes; 60-90 psi for at least 240 minutes; 90-150 psi for at least 1 second; 90-150 psi for at least 1 minute; 90-150 psi for at least 5 minutes; 90-150 psi for at least 15 minutes; 90-150 psi for at least 30 minutes; 90-150 psi for at least 60 minutes; 90-150 psi for at least 90 minutes; 90-150 psi for at least 120 minutes; 90-150 psi for at least 180 minutes; 90-150 psi for at least 240 minutes; 500-700 psi for at least 1 second; 500-700 psi for at least 1 minute; 500-700 psi for at least 5 minutes; 500-700 psi for at least 15 minutes; 500-700 psi for at least 30 minutes; 500-700 psi for at least 60 minutes; 500-700 psi for at least 90 minutes; 500-700 psi for at least 120 minutes; 500-700 psi for at least 180 minutes; 500-700 psi for at least 240 minutes; 1,100-1,300 psi for at least 1 second; 1,100-1,300 psi for at least 1 minute; 1,100-1,300 psi for at least 5 minutes; 1,100-1,300 psi for at least 15 minutes; 1,100-1,300 psi for at least 30 minutes; 1,100-1,300 psi for at least 60 minutes; 1,100-1,300 psi for at least 90 minutes; 1,100-1,300 psi for at least 120 minutes; 1,100-1,300 psi for at least 180 minutes; 1,100-1,300 psi for at least 240 minutes; 150-2,500 psi for at least 1 second; 150-2,500 psi for at least 1 minute; 150- 2,500 psi for at least 5 minutes; 150-2,500 psi for at least 15 minutes; 150-2,500 psi for at least 30 minutes; 150-2,500 psi for at least 60 minutes; 150-2,500 psi for at least 90 minutes; 150-2,500 psi for at least 120 minutes; 150-2,500 psi for at least 180 minutes; or 150-2,500 psi for at least 240 minutes; 2,500-15,000 psi for at least 15 minutes; 2,500- 15,000 psi for at least 30 minutes; 2,500-15,000 psi for at least 60 minutes; 2,500-15,000 psi for at least 90 minutes; 2,500-15,000 psi for at least 120 minutes; 2,500-15,000 psi for at least 180 minutes; 2,500-15,000 psi for at least 240 minutes; 15,000-30,000 psi for at least 15 minutes; 15,000-30,000 psi for at least 30 minutes; 15,000-30,000 psi for at least 60 minutes; 15,000-30,000 psi for at least 90 minutes; 15,000-30,000 psi for at least 120 minutes; 15,000-30,000 psi for at least 180 minutes; or 15,000-30,000 psi for at least 240 minutes.

Combination of Heat and Pressure

[00142] If a process for manufacturing a structural ballistic resistant apparatuses 100 requires both heat and pressure, pressure and heat can be provided simultaneously to reduce the overall cycle time required to manufacture the panel. An autoclave, or other suitable pressurized heated enclosure 42, can facilitate these combined processes. An autoclave is a pressure vessel that can apply elevated pressure and temperature to one or more structural ballistic resistant apparatuses 100 during a process involving the application of heat and pressure. If pressure is applied to the apparatus 100 during the heating process, the process temperature can be modified to account for the effect that pressure has on the melting point of the one or more resins that are incorporated into one or more of the ballistic resistant sheets 50 in the stack 8 or composite layer 505. For instance, if the melting point of the resin increases as pressure increases, the target process temperature required during the heating process can be increased when the heating process occurs in conjunction with the pressure process to ensure melting of the resin.

Heat Sealing

[00143] As discussed above, the stack of ballistic resistant sheets 8 can be encased in a protective cover 1105, as shown in Fig. 5. The outer perimeter of the cover 1105 can be heat-sealed to prevent water ingress. Heat sealing is a process where one material is joined to another (e.g. one thermoplastic is joined to another thermoplastic) using heat and pressure. During the heat sealing process, a heated die or sealing bar can apply heat and pressure to a specific contact area or path to seal or join two materials together. When heat-sealing the perimeter of the cover 1105, the presence of a thermoplastic material proximate the contact area can promote sealing in the presence of heat and pressure. In some examples, the cover 1105 can include thermoplastic polyurethane proximate the contact area to permit heat sealing. The cover 1105 can be made of a first portion and a second portion, and the heat sealing process can be used to join the first portion to the second portion, thereby encapsulating the stack of ballistic resistant sheets in a waterproof enclosure.

Cooling

[00144] After the stack of ballistic resistant sheets 8 and the composite layer 505 has been heated to a predetermined temperature for a predetermined duration, the stack can be cooled. In one example, the cooling process can occur while the stack of ballistic resistant sheets 8 is outside of the vacuum bag 13. In another example, the cooling process can occur while the stack of ballistic resistant sheets 8 is inside the vacuum bag 13 with vacuum applied. In yet another example, the cooling process can occur while the stack of ballistic resistant sheets 8 is inside the vacuum bag 13 with vacuum applied and with pressure applied. During the cooling process, the temperature of the stack of ballistic resistant sheets 8 can be reduced from the predetermined temperature to about 100 degrees Fahrenheit or about 70 degrees Fahrenheit (i.e. room temperature). Cooling can occur through natural convection, forced convection, liquid cooling, or any other suitable cooling process. If liquid cooling is employed, a spray cooling process can be employed. Alternately, the stack of ballistic resistant sheets 8 encased in the waterproof cover 1105 can be submerged in a liquid bath. The liquid bath can be connected to a heat exchanger and pump to increase the rate of cooling.

Assemblies and Modular Systems

[00145] Two or more structural ballistic resistant apparatuses 100 can be combined to form a structural ballistic resistant assembly. The structural ballistic resistant assembly can be sealed with a cover 1105, such as a waterproof covering or encasement. In another example, the structural ballistic resistant assembly can form a modular system where a user can quickly add or remove one or more apparatuses 100 from the assembly. The apparatuses 100 can include hook and loop fasteners (or other suitable fasteners) to permit a user to quickly add or remove apparatuses from the assembly. In one example, a soldier can modify the number of apparatuses 100 in an assembly based on a threat level of a combat situation. If the threat level is higher than expected, the soldier can add one or more additional apparatuses 100 to the assembly, for example, along an exterior or interior surface of a military vehicle. Alternately, if the threat level is lower than expected, the soldier can remove one or more apparatuses 100 from the assembly to reduce the weight of the assembly and thereby enhance the vehicle's mobility.

3 -Dimensional Forming

[00146] Structural ballistic resistant apparatuses 100 can be flat panels (e.g. as shown in Fig. 21) or can be formed into 3-dimensional shapes (e.g. as shown in Fig. 24) through suitable forming processes, such as pressing. Structural ballistic resistant apparatuses 100 are useful in a wide variety of applications where rigid armor is desired. For example, structural ballistic resistant panels 100 can be incorporated into vehicle doors, floors, firewalls, and roofs to protect the vehicle, occupants, equipment, and ammunitions in the vehicle from projectiles. In another example, structural ballistic resistant apparatuses 100 can be incorporated into shields, such as riot shields used by law enforcement personnel.

[00147] In one example, 3-D forming of the structural ballistic panel 100 can occur during the heating process while the panel is in the vacuum bag, as shown in Fig. 22. During the heating process, the apparatus 100 can be placed over a mold and a press 43, such as a hydraulic, pneumatic, or manual press, can apply pressure to a surface of the panel to encourage the panel to conform to the shape of the mold. The apparatus 100 may be permitted to cool in the mold following the 3-D forming process to ensure that lamination of adjacent sheets is complete before the panel is removed from the mold.

[00148] In another example, 3-D forming may occur by arranging non-cured flexible ballistic resistant sheets 50 of the stack 8 into a contoured mold and vacuum bagging the stack of ballistic resistant sheets. The vacuum bagging process can exert a compressive force on the stack 8 that is sufficient to press the ballistic resistant sheets 50 firmly against the mold, thereby causing the stack to assume the geometry of the mold after the heating process is complete. The panel 100 may be permitted to cool in the mold following the 3-D forming process to ensure that lamination of adjacent ballistic sheets and the composite layer 505 is complete before the panel is removed from the mold.

Examples

[00149] The structural ballistic resistant apparatus 100 can be adapted to serve as a load-bearing structure. The apparatus 100 can include a laminated stack of ballistic resistant sheets 8. The laminated stack of ballistic resistant sheets 8 can include a plurality of ballistic sheets 50 arranged to form the stack 8. The laminated stack of ballistic sheets 8 can include a first surface 85 and a second surface 90 opposite the first surface (see, e.g. Fig. 1C). The apparatus 100 can include a structural composite layer 505 having a reinforcing layer 1305 impregnated with a cured matrix material. The structural composite layer 505 can be adjacent to the first surface 85 of the laminated stack of ballistic resistant sheets 8 and the second surface 90 of the laminated stack of ballistic resistant sheets 8. The structural composite layer 505 can encase the laminated stack of ballistic resistant sheets 8, as shown in Fig. IB, and can be configured to serve as a load-bearing structure. In some examples, the flange portion of the structural composite layer 505 shown in Figs. 1A-1C can be trimmed after production of the structural ballistic resistant apparatus 100. For instance, the flange portion can be trimmed flush with one or more side walls 95 of the structural ballistic resistant apparatus 100. The reinforcing layer 1305 can include a woven or nonwoven fabric comprising carbon or glass fibers. The cured matrix material can be a thermoset resin comprises epoxy resin, vinyl-ester resin, or polyester resin. In some examples, the thermoset resin can be cured at a pressure below 10 atmospheres to harden to form, in combination with the reinforcing layer 1305, the structural composite layer 505 that serves as the load- bearing structure surrounding the stack of ballistic resistant sheets 8.

[00150] In some examples, the stack of ballistic sheets 8 can be double wrapped with reinforcing fabric. For instance, the reinforcing layer can include a first sheet of reinforcing fabric 1305, and a second sheet of reinforcing fabric 1405, where the first sheet of reinforcing fabric is wrapped around the outer surface of the laminated stack of ballistic sheets 8, and where the second sheet of reinforcing fabric is wrapped around an outer surface of the first sheet of reinforcing fiber.

[00151] In some examples, the structural composite layer 505 can include a first structural composite layer 110 adhered to the first surface of the laminated stack of ballistic resistant sheets 8, and a second structural composite layer 115 adhered to the second surface of the laminated stack of ballistic resistant sheets 8, where the first structural composite layer 110 is joined to the second structural composite layer 115 around a perimeter of the laminated stack of ballistic resistant sheets 8 to encase the laminated stack of ballistic resistant sheets.

[00152] In some examples, the laminated stack of ballistic resistant sheets 8 can include about 10-20, 15-100, 75-125, at least 100, at least 175, 180-220, 200-260, at least 250, 250-500, 400-600, 500-1,000, or 900-1,200 ballistic resistant sheets. The ballistic resistant sheets 50 can include ultra-high-molecular-weight polyethylene. The ultra-high- molecular-weight polyethylene can have an average molecular weight between about two and six million. The ultra-high-molecular-weight polyethylene can have a melting temperature of about 275-285 degrees F. The ballistic resistant sheets 50 within the laminated stack 8 can include high modulus bidirectional pre-impregnated composite sheets. In other examples, the ballistic resistant sheets 50 can include aramid fibers, ultra-high-molecular-weight polyethylene fabric, or a combination thereof. Where additional ballistic protection or structural integrity is required, the apparatus 100 can include a structural member (e.g. 120, 125) disposed within the structural ballistic resistant apparatus. The structural member can be made of silicon carbide, boron carbide, or metal.

[00153] A method of manufacturing a structural ballistic resistant apparatus 100 can include providing a stack of ballistic resistant sheets 8 and covering at least one surface of the stack of ballistic resistant sheets 8 with a composite layer 505, where the composite layer includes a reinforcing layer 1305 impregnated with a matrix material. The method can include inserting the stack of ballistic resistant sheets 8 and the composite layer 505 into a vacuum bag 13, evacuating gas 32 from the vacuum bag, and heating the stack of ballistic resistant sheets 8 and the composite layer in the vacuum bag 13 to a predetermined temperature for a first predetermined duration to produce a laminated stack of ballistic resistant sheets 8. Through the heating process, the composite layer is transformed into a structural composite layer 505 adapted to be a load-bearing member. The predetermined temperature can be about 125-550, 240-260, or 140-225 degrees Fahrenheit and preferably about 225-275 degrees Fahrenheit. The predetermined duration can be about 15-35, 30-45, 55-125, 120-240, or 220-480 minutes and preferably about 40-90 minutes. The stack of ballistic resistant sheets 8 can include ultra-high- molecular- weight polyethylene fabric. The ultra-high-molecular-weight polyethylene fabric can be a high modulus bidirectional pre-impregnated composite material. In some specific examples, the stack of ballistic resistant sheets 8 can include TENSYLON or ENDUMAX branded ballistic resistant sheets. In some examples, at least one of the ballistic resistant sheets in the stack 8 can include a resin layer with a melting point of about 125-550, 225-275, 240-260, 240-275, or 140-225 degrees F. The method can further include applying a predetermined pressure to the stack of ballistic resistant sheets 8 for a second predetermined duration. The predetermined pressure can be about 40-90, 90-150, 500-700, 1,100-1,300, 150-2,500, 2,500-15,000, or 15,000-30,000 psi and preferably about 60-120 psi. In some examples, heating the stack of ballistic resistant sheets 8 in the vacuum bag 13 to the predetermined temperature for the first predetermined duration can occur concurrently with applying the predetermined pressure to the stack of ballistic resistant sheets in the vacuum bag 13 for the second predetermined duration. In some examples, the method can further include cooling the stack of ballistic resistant sheets 8 in the vacuum bag 13 from the predetermined temperature to about 100 degrees F or about room temperature. The step of providing the stack of ballistic resistant sheets 8 can include providing a stack of about 10-20, 20-100, 100-180, 180-220, 220-260, 260-500, 500-1,000, or 1,000-1,200 ballistic sheets.

[00154] The method can further include positioning the stack of ballistic resistant sheets 8 and the structural composite layer 505 proximate a 3 -dimensional mold and applying pressure to a surface of the composite layer with a press mold 43 to conform the ballistic resistant sheets and the composite layer to the shape of the 3 -dimensional mold.

[00155] A structural ballistic resistant apparatus 100 can be adapted to be a load- bearing structure. The apparatus 100 can include a structural member 120 having an inner surface and an outer surface, where the structural member is a section of tubing, as shown in Figs. 10 or 11. The apparatus 100 can include a laminated stack of ballistic resistant sheets 8 conformed around an outer surface of the structural member 120. The laminated stack of ballistic resistant sheets can have an outer surface, and a structural composite layer 505 can be wrapped around the outer surface of the laminated stack of laminated ballistic resistant sheets 8. The structural composite layer 505 can include a reinforcing layer impregnated with a cured matrix material.

[00156] The structural member can be made of steel, aluminum, titanium, or one or more polymers, such as polyethylene or polypropylene. Where electrical conductivity of the first structural member is desired, such as for heat transfer or data or signal transmission, the structural member can be made of copper. The laminated stack of ballistic resistant sheets 8 can include about 10-20, 20-100, 100-180, 180-220, 220-260, 260-500, 500-1,000, or 1,000-1,200 ballistic sheets. The laminated stack of ballistic resistant sheets can include ultra-high-molecular- weight polyethylene. The ballistic resistant sheets 50 within the laminated stack can be high modulus bidirectional pre- impregnated composite sheets. The reinforcing layer 1305 can include a woven or nonwoven fabric comprising carbon or glass fibers. The cured matrix material can be a thermoset resin made of epoxy resin, vinyl-ester resin, or polyester resin. In some instances, the thermoset resin can be cured at a pressure below 10 atmospheres to harden to form, in combination with the reinforcing layer 1305, the structural composite layer 505 that serves as the load-bearing structure surrounding the stack of ballistic resistant sheets 8. The reinforcing layer 1305 can include a first sheet of reinforcing fabric wrapped around the outer surface of the laminated stack of ballistic sheets, and a second sheet of reinforcing fabric wrapped around an outer surface of the first sheet of reinforcing fiber.

[00157] As can be understood from the foregoing description and the corresponding figures, the basic concepts of the present method may be embodied in a variety of ways. The methods and systems involve numerous and varied embodiments of a laminate, such as a ballistic resistant apparatus including a plurality of laminated ballistic resistant sheets, and methods of producing the laminate.

[00158] As such, the particular embodiments or elements of the method disclosed by the description or shown in the figures or tables accompanying this application are not intended to be limiting, but rather exemplary of the numerous and varied embodiments generically encompassed by the method or equivalents encompassed with respect to any particular element thereof. In addition, the specific description of a single embodiment or element of the method may not explicitly describe all embodiments or elements possible; many alternatives are implicitly disclosed by the description and figures. [00159] It should be understood that each element of an apparatus or each step of a method may be described by an apparatus term or method term. Such terms can be substituted where desired to make explicit the implicitly broad coverage to which this method is entitled. As but one example, it should be understood that all steps of a method may be disclosed as an action, a means for taking that action, or as an element which causes that action. Similarly, each element of an apparatus may be disclosed as the physical element or the action that physical element facilitates. As but one example, the disclosure of "laminate" should be understood to encompass disclosure of the act of "laminating"— whether explicitly discussed or not— and, conversely, were there effectively disclosure of the act of "laminating," such a disclosure should be understood to encompass disclosure of "a laminate" and even a "means for laminating." Such alternative terms for each element or step are to be understood to be explicitly included in the description.

[00160] In addition, as to each term used it should be understood that unless its utilization in this application is inconsistent with such interpretation, common dictionary definitions should be understood to be included in the description for each term as contained in the Random House Webster's Unabridged Dictionary, second edition, each definition hereby incorporated by reference.

[00161] Moreover, for the purposes of the present method, the term "a" or "an" entity refers to one or more of that entity; for example, "a layer of laminatable material" refers to one or more layers of laminatable material. As such, the terms "a" or "an," "one or more," and "at least one" can be used interchangeably herein. Furthermore, an element "selected from the group consisting of refers to one or more of the elements in the list that follows, including combinations of two or more of the elements.

[00162] All numeric values herein are assumed to be modified by the term "about," whether or not explicitly indicated. For the purposes of the methods described herein, ranges may be expressed as from "about" one particular value to "about" another particular value. When such a range is expressed, another embodiment includes from the one particular value to the other particular value. The recitation of numerical ranges by endpoints includes all the numeric values subsumed within that range. A numerical range of one to five includes for example the numeric values 1, 1.5, 2, 2.75, 3, 3.80, 4, 5, and so forth. It will be further understood that the endpoints of each of the ranges are significant both in relation to the other endpoint, and independently of the other endpoint. When a value is expressed as an approximation by use of the antecedent "about," it will be understood that the particular value forms another embodiment. The term "about" generally refers to a range of numeric values that one of skill in the art would consider equivalent to the recited numeric value or having the same function or result. Similarly, the antecedent "substantially" means largely, but not wholly, the same form, manner or degree and the particular element will have a range of configurations as a person of ordinary skill in the art would consider as having the same function or result. When a particular element is expressed as an approximation by use of the antecedent "substantially," it will be understood that the particular element forms another embodiment.

[00163] Thus, the applicant(s) should be understood to claim at least: i) each of the laminates and ballistic resistant panels herein disclosed and described, ii) the related methods disclosed and described, iii) similar, equivalent, and even implicit variations of each of these devices and methods, iv) those alternative embodiments which accomplish each of the functions shown, disclosed, or described, v) those alternative designs and methods which accomplish each of the functions shown as are implicit to accomplish that which is disclosed and described, vi) each feature, component, and step shown as separate and independent methods, vii) the applications enhanced by the various systems or components disclosed, viii) the resulting products produced by such systems or components, ix) methods and apparatuses substantially as described hereinbefore and with reference to any of the accompanying examples, x) the various combinations and permutations of each of the previous elements disclosed.

Claims

CLAIMS What is claimed is:

1. A structural ballistic resistant apparatus configured to serve as a load-bearing structure, the apparatus comprising:

a plurality of laminated ballistic resistant sheets arranged to form a stack of laminated ballistic resistant sheets, the stack of laminated ballistic sheets comprising a first surface and a second surface opposite the first surface; and a structural composite layer covering and conforming to the first surface of the stack of laminated ballistic sheets, the structural composite layer comprising a reinforcing layer and a matrix material, the structural composite layer configured to serve as a load-bearing structure.

2. The structural ballistic resistant apparatus of claim 1, wherein the reinforcing layer comprises a woven or nonwoven fabric comprising carbon or glass fibers.

3. The structural ballistic resistant apparatus of claim 1, wherein the matrix material is a thermoset resin comprising epoxy resin, vinyl-ester resin, or polyester resin.

4. The structural ballistic resistant apparatus of claim 1, wherein the structural composite layer covers and conforms to the second surface of the stack of laminated ballistic sheets.

5. The structural ballistic resistant apparatus of claim 4, wherein the structural composite layer comprises:

a first structural composite layer covering and conforming to the first surface of the stack of laminated ballistic resistant sheets, and

a second structural composite layer covering and conforming to the second surface of the stack of laminated ballistic resistant sheets, wherein the first structural composite layer is joined to the second structural composite layer around a perimeter of the stack of laminated ballistic resistant sheets to encase the stack of laminated ballistic resistant sheets.

6. The structural ballistic resistant apparatus of claim 1, wherein the reinforcing layer comprises:

a first sheet of reinforcing fabric wrapped around an outer surface of the stack of laminated ballistic sheets; and

a second sheet of reinforcing fabric wrapped around an outer surface of the first sheet of reinforcing fiber.

7. The structural ballistic resistant apparatus of claim 1, wherein the stack of laminated ballistic resistant sheets comprises about 10-20, 15-100, 75-125, at least 100, at least 175, 180-220, 200-260, at least 250, 250-500, 400-600, 500-1,000, or 900-1,200 ballistic resistant sheets.

8. The structural ballistic resistant apparatus of claim 7, wherein the ballistic resistant sheets comprise ultra-high-molecular-weight polyethylene.

9. The structural ballistic resistant apparatus of claim 8, wherein the ballistic resistant sheets within the stack of laminated ballistic resistant sheets comprise high modulus bidirectional pre-impregnated composite sheets.

10. The structural ballistic resistant apparatus of claim 8, wherein the ultra-high- molecular-weight polyethylene has an average molecular weight between about two and six million, and wherein the ultra-high-molecular-weight polyethylene has a melting temperature of about 275-285 degrees F.

11. The structural ballistic resistant apparatus of claim 7, wherein the ballistic resistant sheets comprise aramid fibers.

12. The structural ballistic resistant apparatus of claim 1, further comprising a first structural member disposed within the structural ballistic resistant apparatus, the first structural member comprising ceramic or metal.

13. A method of manufacturing a structural ballistic resistant apparatus, the method comprising:

providing a stack of ballistic resistant sheets; covering at least one surface of the stack of ballistic resistant sheets with a composite layer, the composite layer comprising a reinforcing layer impregnated with a matrix material;

inserting the stack of ballistic resistant sheets and the composite layer into a variable volume container;

evacuating gas from the variable volume container; and

heating the stack of ballistic resistant sheets and the composite layer in the variable volume container to a predetermined temperature for a first predetermined duration to produce a stack of laminated ballistic resistant sheets, wherein, through the heating process, the composite layer transforms into a structural composite layer adapted to be a load-bearing member.

14. The method of claim 13, wherein the predetermined temperature is about 125-550, 225-275, 240-260, or 140-225 degrees Fahrenheit and the predetermined duration is about 15-35, 30-45, 40-90, 55-125, 120-240, or 220-480 minutes.

15. The method of claim 13, wherein the stack of ballistic resistant sheets comprises ultra-high-molecular-weight polyethylene fabric.

16. The method of claim 15, wherein the stack of ballistic resistant sheets comprises aramid fibers.

17. The method of claim 15, wherein the stack of ballistic resistant sheets comprises TENSYLON or ENDUMAX ballistic resistant sheets.

18. The method of claim 13, wherein at least one of the ballistic resistant sheets comprises a resin layer with a melting point of about 125-550, 225-275, 240-260, 240- 275, or 140-225 degrees F.

19. The method of claim 13, further comprising applying a predetermined pressure to the stack of ballistic resistant sheets for a second predetermined duration.

20. The method of claim 19, wherein the predetermined pressure is about 40-90, 60-120, 90-150, 500-700, 1,100-1,300, 150-2,500, 2,500-15,000, or 15,000-30,000 psi.

21. The method of claim 19, wherein heating the stack of ballistic resistant sheets in the variable volume container to the predetermined temperature for the first predetermined duration occurs concurrently with applying the predetermined pressure to the stack of ballistic resistant sheets in the variable volume container for the second predetermined duration.

22. The method of claim 13, further comprising cooling the stack of ballistic resistant sheets in the variable volume container from the predetermined temperature to about 100 degrees F or about room temperature.

23. The method of claim 13, wherein providing the stack of ballistic resistant sheets comprises providing a stack of about 10-20, 20-100, 100-180, 180-220, 220-260, 260-500, 500-1,000, or 1,000-1,200 ballistic sheets.

24. The method of claim 13, further comprising positioning the stack of ballistic resistant sheets and the composite layer proximate a 3 -dimensional mold and applying pressure to the composite layer with a press mold to conform the stack of ballistic resistant sheets and the composite layer to the shape of the 3 -dimensional mold.

25. A structural ballistic resistant apparatus adapted to be a load-bearing structure, the apparatus comprising:

a structural member comprising an inner surface and an outer surface, wherein the structural member is a section of tubing;

a plurality of laminated ballistic resistant sheets arranged to form a stack of laminated ballistic resistant sheets, the stack of laminated ballistic resistant sheets conformed around an outer surface of the structural member, the stack of laminated ballistic resistant sheets comprising an outer surface; and

a structural composite layer conformed around the outer surface of the stack of laminated ballistic resistant sheets, the structural composite layer comprising a reinforcing layer impregnated with a cured matrix material.

26. The structural ballistic resistant apparatus of claim 25, wherein the structural member comprises steel, aluminum, copper, titanium, or plastic.

27. The structural ballistic resistant apparatus of claim 25, wherein the stack of laminated ballistic resistant sheets comprises about 10-20, 20-100, 100-180, 180-220, 220-260, 260-500, 500-1,000, or 1,000-1,200 ballistic sheets.

28. The structural ballistic resistant apparatus of claim 25, wherein the stack of laminated ballistic resistant sheets comprises ultra-high-molecular-weight polyethylene.

29. The structural ballistic resistant apparatus of claim 25, wherein the reinforcing layer comprises a woven or nonwoven fabric comprising carbon or glass fibers.

30. The structural ballistic resistant apparatus of claim 25, wherein the cured matrix material is a thermoset resin comprising epoxy resin, vinyl-ester resin, or polyester resin.