CN102930862B - Z-direction enhanced underwater sound absorption sandwich composite material and preparation method for same - Google Patents
Z-direction enhanced underwater sound absorption sandwich composite material and preparation method for same Download PDFInfo
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- CN102930862B CN102930862B CN201210368665.9A CN201210368665A CN102930862B CN 102930862 B CN102930862 B CN 102930862B CN 201210368665 A CN201210368665 A CN 201210368665A CN 102930862 B CN102930862 B CN 102930862B
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Abstract
The invention discloses a Z-direction enhanced underwater sound absorption sandwich composite material and a preparation method for the same. The composite material comprises composite material panels, a sound absorption core material and enhancement structures, wherein the enhancement structures are arranged in the thickness direction of the sound absorption core material, namely a Z direction, between the upper and lower panels. The whole structure of the Z-direction enhanced underwater sound absorption sandwich composite material is formed by a vacuum assisted forming process. Compared with an ordinary sound absorption sandwich composite material, the Z-direction enhanced underwater sound absorption sandwich composite material has the advantages that flat compression strength is greatly strengthened, a compression modulus is improved by more than one order of magnitude, bending rigidity is doubled, sound absorption performance is improved by 10 to 85 percent, and sound absorption performance under high water pressure is improved by 50 to 85 percent; and the forming process has the advantages of high operability, high quality consistency, suitability for the formation of a large-sized composite material component, and the like.
Description
Technical field
The present invention relates to a kind of underwater sound absorption composite technology, particularly a kind of Z-direction strengthens underwater sound absorption core filled composite material and preparation method thereof.
Background technology
At present, a kind of employing is fiber reinforced resin based provides a kind of Z-direction to strengthen underwater sound absorption core filled composite material and preparation method thereof again, solve existing underwater sound absorption core filled composite material and cannot take into account the problem of structural bearing performance and sound absorbing capabilities completely, realize the high structural bearing performance of underwater sound absorption compound substance and the integrated condensation material of high acoustic absorption performance as panel, adopt rubber, polyurethane, the elastic bodys such as flexible-epoxy are sound absorption core, there is structural bearing and the integrated sandwich structure composite material of sound absorption, substituting gradually the sound absorption structure of original " steel+anechoic coatings ", realize loss of weight, stealthy, erosion-resisting comprehensive object, become one of important development trend of following underwater sound absorption structure.
Possess structural bearing and the integrated underwater sound absorption structure of sound absorption, must possess enough rigidity, hydraulic pressure resistance ability and excellent sound absorbing capabilities, the height of these performances depends primarily on sandwich layer, as the strength and modulus that improves sandwich layer can effectively improve rigidity, the hydraulic pressure resistance ability of sandwich structure, the strength and modulus that reduces sandwich layer is conducive to improve dissipation factor, and then improves the sound absorbing capabilities of sandwich structure.Obviously, the sound absorbing capabilities that improves the rigidity, hydraulic pressure resistance ability of sound absorption structure simultaneously and improve sound absorption structure is contradiction.Because watertight material protection is conveniently used at the edge of sound absorption structure, and very limited on sound absorbing capabilities impact, hydraulic pressure is negligible on the impact of the side of sound absorption structure, so the focus of contradiction concentrates on the thickness direction (Z-direction) of sound absorption structure.
For above problem, scholars have carried out a large amount of research in recent years.Modal method has three kinds; The one, in order to take into account structural behaviour and sound absorbing capabilities, designing and preparing in the process of structural bearing and the integrated sandwich structure composite material of sound absorption, structural mechanical property and the sound absorbing capabilities of loss part simultaneously, this method has caused obtaining sound absorption structure under high performance structural carrying and sound absorption integrated water, has limited the usable range of this structure; The 2nd, there is metallic framework, and when the length of metallic framework and width are less than 300mm, by improving thickness, the modulus of compound substance, carry out the integrated of implementation structure carrying and sound absorption, this method has obvious limitation, and the thickness increase of compound substance can reduce sound absorbing capabilities to a certain extent; The 3rd, in sound absorption structure, increase compound substance skeleton, as mentioned the method in document " experimental study of the stealthy sandwich composite structure of underwateracoustic acoustic characteristic ", although this method is conducive to improve anti-pressure ability and the integrally-built rigidity of Z-direction, but technique is loaded down with trivial details, be difficult to engineering application, especially to curved-surface structure, in addition, compound substance skeleton can increase considerably the weight of sound absorption structure, is unfavorable for the maneuverability of loss of weight and raising submarine navigation device.
Summary of the invention
Technical matters to be solved by this invention is to provide a kind of Z-direction and strengthens underwater sound absorption core filled composite material and preparation method thereof, solve existing underwater sound absorption core filled composite material and cannot take into account the problem of structural bearing performance and sound absorbing capabilities completely, the high structural bearing performance and the high acoustic absorption performance that realize underwater sound absorption compound substance are integrated.
In order to realize the object solving the problems of the technologies described above, the present invention has adopted following technical scheme:
Z-direction of the present invention strengthens underwater sound absorption core filled composite material, comprise composite material face, sound absorption core and in the above between plate and lower panel, the thickness direction of sound absorption sandwich layer is the enhancing structure that Z-direction arranges, the one-piece construction of Z-direction enhancement mode underwater sound absorption core filled composite material adopts vacuum assistant resin infused moulding; Described panel is divided into top panel and lower panel, they are fabric and strengthen polymer matrix composites, its reinforcing material is first-selected but be not limited only to the hybrid fabrics of S glass fabric or carbon fiber and S glass fibre, and fabric construction includes but are not limited to plain, twill, satin and multi-axial tricot; Resin matrix be viscosity lower than epoxy resin or the vinylite of 800mPas, the curing employing amine curing agent of epoxy resin; Vinylite adopts superoxide, cobalt ions promoter curing system; The fibre weight content of top panel and lower panel is 50～65%; Strengthen structure and include but are not limited to fibre reinforced composites post, titanium bar (pin), stainless steel (pin); Described sound absorption sandwich layer is elastomeric material, includes but are not limited to rubber, polyurethane, flexible-epoxy material.
The elastomeric material of described sound absorption sandwich layer includes but are not limited to the homogeneous material of solid homogeneous material, solid impedance transition mechanism functionally gradient material (FGM), built-in difformity operatic tunes structure and the impedance transition mechanism functionally gradient material (FGM) of built-in difformity operatic tunes structure.
Described sound absorption sandwich layer core upper surface and lower surface are equipped with unidirectional groove, and groove cross section is semicircle, rectangle, triangle, and spacing is 10 mm～60mm.Groove can be reserved in the moulding of sound absorption sandwich layer, also can after moulding, adopt machine-tooled method to obtain.
Preferred enhancing structure is fibre reinforced composites post, the first-selected continuous fiber of reinforcing material of composite wood stock column, the inferior chopped strand that selects, the fortifying fibre of applicable this patent includes but are not limited to glass fibre, carbon fiber, Kafra fiber, superhigh molecular weight polyethylene fibers and basalt fibre, and resin matrix is consistent with the matrix of composite material face.
Described enhancing structure is that dot matrix distributes, and distribution form includes but are not limited to rectangle, rhombus, strengthens the cross section circular of structure, and its diameter is 2mm～10mm, and spacing is 10mm～60mm.
The forming method that Z-direction described in this patent strengthens underwater sound absorption core filled composite material comprises successively:
(1) sound absorption sandwich layer preformed: rubber matrix sound absorption sandwich layer adopts mould pressing process moulding; Sound absorption sandwich layer has reserved groove or has through hole; Polyurethane, flexible-epoxy matrix sound absorption sandwich layer adopts pouring forming technology moulding, solidifies, after the demoulding, repairs;
(2) machine drilling: for for being reserved with the sound absorption sandwich layer of through hole, according to the hole distribution of design, in the groove of sound absorption sandwich layer, adopt the method for machine drilling to open hole, the diameter in hole is 2mm～10mm;
(3) technique of entrying of sound absorption sandwich layer: drive continuous fiber tow by the through hole of sound absorption sandwich layer with draw point, make fibre bundle be full of each through hole and the groove on sound absorption sandwich layer;
(4) in sound absorption sandwich layer, embed titanium bar or stainless steel: this step is the alternative steps of step (3), by smearing structure glue on titanium bar or stainless steel, embedded in the through hole of sound absorption sandwich layer, solidify finishing;
(5) integrally-built vacuum assistant resin infused moulding: this step is vacuum assistant resin infused, the fabric that technological process comprises cutting and dried fibres fabric, prepares release cloth, flow-guiding cloth, pitch tube, vacuum tube, vacuum bag film, paving cover lower panel, lays fabric that sound absorption sandwich layer, paving be covered with panel, arranges release cloth and flow-guiding cloth, lays pitch tube and vacuum tube, employing vacuum bag film and sealant tape sealing, batching and bubble removing, perfusion resin under vacuum condition, solidifies.The length that the difference of this moulding process and general vacuum assistant resin infused is flow-guiding cloth is determined by the size of groove.
By adopting technique scheme, the present invention has following beneficial effect:
Z-direction of the present invention strengthens underwater sound absorption core filled composite material and compares with existing underwater sound absorption core filled composite material, flat crushing strength increases substantially, modulus in compression has improved one more than the order of magnitude, bending stiffness is doubled, sound absorbing capabilities improves 10～85%, especially the sound absorbing capabilities under high hydraulic pressure has improved 50～85%, solve existing underwater sound absorption compound substance and cannot take into account the problem of structural bearing performance and sound absorbing capabilities completely, realized the integrated of high structural bearing performance and high acoustic absorption performance.
That the preparation method that Z-direction strengthens underwater sound absorption core filled composite material has is workable, quality conformance good, be applicable to the advantages such as large-scale composite material molding component, can be used for the construction of acoustic absorption composite material member for submarine navigation device.
Accompanying drawing explanation
Fig. 1 is that Z-direction strengthens one of underwater sound absorption core filled composite material beam, plate, hull structure component schematic diagram.
Fig. 2 be Z-direction strengthen underwater sound absorption core filled composite material beam, plate, hull structure component schematic diagram two.
Fig. 3 is the enhancing structure of the Z-direction of sound absorption sandwich layer and surperficial groove schematic diagram.
Fig. 4 is in embodiment 1, two kinds of underwater sound absorption core filled composite materials Sound absorbing spectrum under normal pressure.
Fig. 5 is in embodiment 1, two kinds of underwater sound absorption core filled composite materials Sound absorbing spectrum under 3.0MPa.
Fig. 6 is in embodiment 1, two kinds of underwater sound absorption core filled composite materials Sound absorbing spectrum under 4.5MPa.
In accompanying drawing: 1 is composite material face, comprise fiberglass panel, carbon fiber panel, assorted fibre panel etc.; 2 for sound absorption core, comprises rubber sound absorption material, polyurethane sound absorption material, flexible-epoxy acoustic absorbant etc.; 3 for strengthening structure, comprises the titanium bar (pin), stainless steel (pin) of fibre reinforced composites post, seawater corrosion resistance etc.; 4 is groove, comprises square-section groove, semi-circular cross-section groove, open-delta section grooves etc.; 5 is the Sound absorbing spectrum of general sandwich structure acoustic absorption composite material; 6 Sound absorbing spectrums for Z-direction enhancing underwater sound absorption core filled composite material.
Embodiment
Below in conjunction with accompanying drawing, this patent is further explained.But the protection domain of this patent is not limited to concrete embodiment.
Embodiment mono-
Z-direction in the present embodiment strengthens underwater sound absorption core filled composite material, it by glass fibre reinforced composion upper and lower panel, absorb sound sandwich layer and the glass fibre reinforced composion post that is arranged between upper and lower panel forms.The formula of top panel and lower panel is: matrix resin SWANCOR901-200 is 3.0kg, hardening agent is that MEKP is 0.06kg, promoter naphthoic acid cobalt 0.009kg, and fortifying fibre is S2 twills, fibre weight content 60～62%, is of a size of 500mm х 500mm х 5mm, sound absorption sandwich layer formula is: epoxy resin-base be 6kg(wherein E51 be 2.4kg, 6350 is 3.6kg), filler is wherein glass flake 1.2kg of 2.4kg(, vermiculite power 0.6kg, semi-reinforcing hydrocarbon black 0.3kg, white carbon 0.3kg), epoxy hardener 5784 is 2.4kg, coupling agent KH550 is 0.06kg, sandwich layer is of a size of 500mm х 500mm х 40mm, core upper surface and lower surface are equipped with unidirectional groove, flute pitch is 20mm, recess width is 5mm, the degree of depth is 2mm, thickness direction along core is provided with circular perforations, perforation quadrature, vertically arrange, Kong Zhongwei compound substance cylinder, its formula is: matrix resin SWANCOR901-200 is 3.0kg, hardening agent is that MEKP is 0.06kg, promoter naphthoic acid cobalt 0.009kg, fortifying fibre is the E glass fibre yarn bundle of 10000 Tex, fibre weight content is 50%, diameter is 5mm.
It is as follows that Z-direction in the present embodiment strengthens underwater sound absorption core filled composite material forming method:
(1) flexible epoxy of modification sound absorption sandwich layer preformed.By said ratio weighing raw materials, add successively matrix resin, filler, coupling agent, hardening agent, mix, bubble removing, be poured in the mould of getting ready, solidify, the demoulding, finishing.Sound absorption sandwich layer after the demoulding has the reserved groove of design.
(2) machine drilling.In the groove of sound absorption sandwich layer, adopt the method for machine drilling to open hole, the diameter in hole is 5mm, spacing 20mm.
(3) technique of entrying of sound absorption sandwich layer.Adopt custom-designed draw point, drive continuous fiber tow by the through hole of sound absorption sandwich layer, make fibre bundle be full of each through hole and the groove on sound absorption sandwich layer.
(4) integrally-built vacuum assistant resin infused moulding.Technological process comprises cutting and dried fibres fabric, prepare release cloth, flow-guiding cloth, pitch tube, vacuum tube, vacuum bag film etc. auxiliary with material, paving is covered the fabric of lower panel, lay sound absorption sandwich layer, paving is covered with the fabric of panel, arranges release cloth and flow-guiding cloth, lays pitch tube and vacuum tube, employing vacuum bag film and sealant tape sealing, batching and bubble removing, perfusion resin under vacuum condition, the process such as solidifies.
The Z-direction that obtains in the present embodiment strengthen underwater sound absorption core filled composite material with the structural behaviour of sandwich structure composite material of generally taking into account structural bearing and sound absorption to such as table 1, underwater sound absorption performance is respectively as Fig. 4, Fig. 5, Fig. 6.
The structural behaviour contrast of the general sandwich structure acoustic absorption composite material of table 1 and the embodiment of the present invention one technology
| Contrast project | Flat crushing strength | Modulus in compression | Bending stiffness |
| Generally take into account the sandwich structure composite material of structural bearing and sound absorption | Flat crushing strength under 10% deflection is 3.1MPa | 33MPa | 5.7E+8 N/mm 2 |
| The material of preparation in embodiment mono- | Flat crushing strength under 2% deflection is 6MPa | 400MPa | 1.2E+9 N/mm 2 |
There are table 1, Fig. 4, Fig. 5, Fig. 6 to know, compare the sandwich structure composite material of generally taking into account structural bearing and sound absorption, the flat crushing strength of Z-direction enhancement mode underwater sound absorption core filled composite material of the present invention increases substantially, modulus in compression has improved that an order of magnitude is above, bending stiffness is doubled, within the scope of 2kHz～30kHz, under normal pressure, sound absorbing capabilities improves sound absorbing capabilities under 20%, 3.0MPa hydraulic pressure and has improved approximately 54%, and under 4.5MPa hydraulic pressure, sound absorbing capabilities has improved approximately 83%.
Embodiment bis-
The difference of the present embodiment and embodiment mono-sandwich layer that is to absorb sound is polyurethane elastomer material, and other compositions, version, preparation method are identical with embodiment mono-.
Structural behaviour in the present embodiment is consistent with increase rate and the embodiment mono-of underwater sound absorption performance.
Embodiment tri-
The present embodiment and embodiment mono-or twos' the difference sandwich layer that is to absorb sound is synthetic rubber, and the moulding process of rubber sound absorption material is die press technology for forming.Other compositions, version, preparation method are identical with embodiment mono-or two.
Claims (8)
1. a Z-direction strengthens underwater sound absorption core filled composite material, it is characterized in that: comprise composite material face, sound absorption core and in the above between plate and lower panel, the thickness direction of sound absorption sandwich layer is the enhancing structure that Z-direction arranges, the one-piece construction that Z-direction strengthens underwater sound absorption core filled composite material adopts vacuum assistant resin infused moulding; Described panel is divided into top panel and lower panel, they are high-performance fiber fabric and strengthen polymer matrix composites, its reinforcing material is the hybrid fabrics of S glass fabric or carbon fiber and S glass fibre, and fabric construction is plain, twill, satin or multi-axial tricot; Resin matrix be viscosity lower than epoxy resin or the vinylite of 800mPas, the curing employing amine curing agent of epoxy resin; Vinylite adopts superoxide, cobalt ions promoter curing system; The fibre weight content of top panel and lower panel is 50～65%; Strengthen structure for dimension reinforced composite post, titanium bar, titanium pin, stainless steel or stainless pin; Described sound absorption sandwich layer is elastomeric material.
2. Z-direction strengthens underwater sound absorption core filled composite material according to claim 1, it is characterized in that: the elastomeric material of described sound absorption sandwich layer is rubber, polyurethane, flexible-epoxy material.
3. Z-direction strengthens underwater sound absorption core filled composite material according to claim 1, it is characterized in that: the elastomeric material of described sound absorption sandwich layer is the homogeneous material of solid homogeneous material, solid impedance transition mechanism functionally gradient material (FGM), built-in difformity operatic tunes structure or the impedance transition mechanism functionally gradient material (FGM) of built-in difformity operatic tunes structure.
4. Z-direction strengthens underwater sound absorption core filled composite material according to claim 1, it is characterized in that: described sound absorption sandwich layer core upper surface and lower surface are equipped with unidirectional groove, and groove cross section is semicircle, rectangle, triangle, and spacing is 10 mm～60mm; Groove is reserved when the moulding of sound absorption sandwich layer, or after moulding, adopts machine-tooled method to obtain.
5. Z-direction strengthens underwater sound absorption core filled composite material according to claim 1, it is characterized in that: described enhancing structure is fibre reinforced composites post, and the reinforcing material of composite wood stock column is continuous fiber or chopped strand.
6. Z-direction strengthens underwater sound absorption core filled composite material according to claim 5, it is characterized in that: the reinforcing material of described composite wood stock column is glass fibre, carbon fiber, Kafra fiber, superhigh molecular weight polyethylene fibers or basalt fibre, and resin matrix is consistent with the matrix of composite material face.
7. Z-direction strengthens underwater sound absorption core filled composite material according to claim 1, it is characterized in that: described enhancing structure is that dot matrix distributes, and distribution form is rectangle or rhombus, and the cross section that strengthens structure is circular, its diameter is 2mm～10mm, and spacing is 10mm～60mm.
8. described in claim 1, Z-direction strengthens the forming method of underwater sound absorption core filled composite material, it is characterized in that: forming method comprises successively:
(1) sound absorption sandwich layer preformed: rubber matrix sound absorption sandwich layer adopts mould pressing process moulding; Sound absorption sandwich layer has reserved groove or has through hole; Polyurethane, flexible-epoxy matrix sound absorption sandwich layer adopts pouring forming technology moulding, solidifies, after the demoulding, repairs;
(2) machine drilling: for for being reserved with the sound absorption sandwich layer of through hole, according to the hole distribution of design, in the groove of sound absorption sandwich layer, adopt the method for machine drilling to open hole, the diameter in hole is 2mm～10mm;
(3) technique of entrying of sound absorption sandwich layer: drive continuous fiber tow by the through hole of sound absorption sandwich layer with draw point, make fibre bundle be full of each through hole and the groove on sound absorption sandwich layer;
(4) in sound absorption sandwich layer, embed titanium bar or stainless steel: this step is the alternative steps of step (3), by smearing structure glue on titanium bar or stainless steel, embedded in the through hole of sound absorption sandwich layer, solidify finishing;
(5) integrally-built vacuum assistant resin infused moulding: this step is vacuum assistant resin infused, technological process comprises cutting and dried fibres fabric; Prepare release cloth, flow-guiding cloth, pitch tube, vacuum tube, vacuum bag film; Paving is covered the fabric of lower panel; Lay sound absorption sandwich layer; Paving is covered with the fabric of panel; Arrange release cloth and flow-guiding cloth; Lay pitch tube and vacuum tube; Adopt vacuum bag film and sealant tape sealing; Batching and bubble removing; Perfusion resin under vacuum condition; Solidify.
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Families Citing this family (9)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN104070717B (en) * | 2014-06-24 | 2016-06-08 | 赤峰恒裕型钢有限公司 | Chromatic steel sandwich plate and its preparation method |
| CN104616647A (en) * | 2014-12-26 | 2015-05-13 | 北京市劳动保护科学研究所 | Composite sound absorption structure |
| CN104616648A (en) * | 2014-12-26 | 2015-05-13 | 北京市劳动保护科学研究所 | Composite sound absorption plate |
| CN106626435A (en) * | 2016-11-28 | 2017-05-10 | 中国民用航空总局第二研究所 | Foam sandwich composite material for aviation dining car and preparation method of foam sandwich composite material |
| CN108051820A (en) * | 2017-12-28 | 2018-05-18 | 武汉长江航道救助打捞局 | A kind of sound identification item and the method for arranging quality testing under water using sound identification item progress |
| CN108492814A (en) * | 2018-03-28 | 2018-09-04 | 贵州大学 | A kind of combination cavity type acoustic stimulation based on impedance transition mechanism type |
| CN108520739A (en) * | 2018-03-28 | 2018-09-11 | 贵州大学 | A kind of impedance transition mechanism type acoustic stimulation based on locally resonant principle |
| CN110176224B (en) * | 2019-06-20 | 2021-07-30 | 南京航空航天大学 | Pyramid-shaped lattice reinforced cavity type underwater sound absorption structure |
| CN110288971B (en) * | 2019-06-20 | 2022-03-15 | 南京航空航天大学 | Straight column type lattice enhanced local resonance underwater sound absorption structure |
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| KR20070072958A (en) * | 2006-01-03 | 2007-07-10 | 신승종 | A structure for reducing the noise transmitted through apartment slab |
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| CN101719367A (en) * | 2009-12-01 | 2010-06-02 | 中国人民解放军海军工程大学 | Low-density underwater sound absorbing plate and preparation method thereof |
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