CN111390033A - Device and method for preparing hot-formed part - Google Patents
Device and method for preparing hot-formed part Download PDFInfo
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- CN111390033A CN111390033A CN202010210575.1A CN202010210575A CN111390033A CN 111390033 A CN111390033 A CN 111390033A CN 202010210575 A CN202010210575 A CN 202010210575A CN 111390033 A CN111390033 A CN 111390033A
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- die
- steel plate
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/16—Heating or cooling
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
- B21D22/02—Stamping using rigid devices or tools
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
- B21D37/00—Tools as parts of machines covered by this subclass
- B21D37/10—Die sets; Pillar guides
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B24—GRINDING; POLISHING
- B24C—ABRASIVE OR RELATED BLASTING WITH PARTICULATE MATERIAL
- B24C1/00—Methods for use of abrasive blasting for producing particular effects; Use of auxiliary equipment in connection with such methods
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Shaping Metal By Deep-Drawing, Or The Like (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention relates to a device and a method for preparing a hot forming part. The preparation method comprises the following steps: flowing a cooling liquid in the first channel and the second channel; enabling the first mold and the second mold to be in an opening state; providing a steel plate heated to be above the austenitizing temperature, and placing the steel plate on the top surface of the second die, wherein the steel plate is a to-be-connected area of the steel plate corresponding to the first groove and the second groove; operating the preparation device to enable the first die and the second die to be in a closed state and keep the closed state until the area of the steel plate outside the area to be connected is cooled to be below the Ms temperature; and operating the preparation device, opening the first die and the second die, and taking out the part formed by hot stamping the steel plate. The hardness of the to-be-connected area of the hot forming part prepared by the invention is obviously lower than that of other areas of the part, and the subsequent position is convenient for mechanical connection with other materials such as self-piercing riveting, hot melting self-tapping and the like, is convenient for positioning, and can ensure the strength of a joint.
Description
Technical Field
The invention belongs to the technical field of hot forming, and particularly relates to a hot forming part preparation device and a preparation method.
Background
Due to energy saving and environmental protection requirements, the light weight of automobiles has become a development trend. The light weight of the automobile means that the quality of the automobile is reduced as much as possible on the premise of ensuring the collision safety and the vehicle performance, thereby improving the dynamic property of the automobile, reducing the fuel consumption and reducing the exhaust pollution.
In order to meet the requirement of light weight of the vehicle body, the application of the vehicle body made of mixed materials and high-strength steel is a development trend. On one hand, light materials such as aluminum alloys are increasingly applied to vehicle bodies; on the other hand, the application proportion of high-strength steel, particularly hot forming steel is increasing continuously, and the highest strength of the hot forming steel reaches 2000MPa at present.
Generally, a hot formed part is prepared by heating a hot formed steel plate to an austenitizing state, rapidly transferring the hot formed steel plate into a die for press forming, and quenching the hot formed steel plate in the die with a cooling water channel at an extremely fast cooling speed under a certain pressure to finally obtain an ultra-high strength part with a uniform martensite structure.
In the manufacture of vehicle bodies, aluminum alloys are typically mechanically joined to steel sheets. However, since the hot formed steel forms martensite after quenching, the strength is usually more than 1300MPa, and the traditional mechanical connection process is difficult to connect the hot formed steel. For example: rivets in self-piercing riveting and hot-melting self-tapping processes cannot effectively pierce hot-formed steel.
In order to solve the problems, in order to realize the connection between the hot forming steel and the aluminum alloy, holes can be cut by laser at the parts to be connected of the hot forming steel, then rivets are inserted from prefabricated holes at one side of the hot forming steel, and then the holes are mechanically connected with the aluminum alloy. The technology has the problems of difficult positioning, low joint strength and the like.
Therefore, improvements in the prior art are needed.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a device and a method for preparing a hot forming part, which are used for solving the problems that the strength of the connecting position of hot forming steel and aluminum alloy is high and the subsequent mechanical connection is difficult in the prior art.
The invention realizes the purpose through the following technical scheme:
first, the present invention provides a thermoformed part manufacturing apparatus, comprising:
the second die is fixedly arranged, a plurality of through second channels are arranged at intervals along the horizontal direction, and a second groove is formed in the top surface of the second die;
the first mould is arranged right above the second mould in an openable and closable manner, a plurality of through first channels are horizontally arranged on the first mould at intervals, a first groove is formed in the bottom surface of the first mould, the first groove corresponds to the second groove, and the first groove corresponds to the second groove.
Further, the top surface of the second mold is provided with a plurality of second grooves, and correspondingly, the bottom surface of the first mold is provided with a plurality of first grooves corresponding to the second grooves.
Furthermore, the first groove and the second groove are both circular in shape, and the depth of the first groove and the depth of the second groove are greater than or equal to 1 mm.
Furthermore, the first die and the second die are both made of die steel.
In another aspect, the present invention also provides a method of making a thermoformed part, the method comprising:
providing cooling liquid, and enabling the cooling liquid to flow in the first channel and the second channel;
operating the preparation device to enable the first mold and the second mold to be in an opening state;
providing a steel plate heated to above an austenitizing temperature, and placing the steel plate on the top surface of the second die, wherein the steel plate is a region to be connected of the steel plate corresponding to the first groove and the second groove;
operating the preparation device to bring the first mold and the second mold into a closed state;
operating the preparation device to keep the first die and the second die in a closed state until the region of the steel plate outside the region to be connected is cooled to be below the Ms temperature, and finishing the steel plate quenching process;
and operating the preparation device, opening the first die and the second die, and taking out the part formed by hot stamping the steel plate.
Further, the steel sheet is a hot-formed steel sheet.
Optionally, removing the part formed by hot stamping the steel plate further comprises:
and (4) carrying out shot blasting on the hot stamped part.
Optionally, the surface of the steel sheet has a plating layer.
Further, the plating layer is an AlSi plating layer or a GI plating layer.
Further, the cooling liquid is water.
The invention has the beneficial effects that:
according to the hot forming part preparation device and the hot forming part prepared by the preparation method disclosed by the invention, the structure of the to-be-connected area of the steel plate is mainly one or more of ferrite, pearlite, bainite and other structures, the structure of the steel plate outside the to-be-connected area is mainly martensite, the hardness of the to-be-connected area is obviously lower than that of other areas of the part, and as the hardness of the to-be-connected area is reduced, the subsequent position is convenient for mechanical connection such as self-piercing riveting, hot-melting self-tapping and the like with other materials, the positioning is convenient, and the joint strength can be ensured.
Drawings
In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.
FIG. 1 is a schematic structural view of a hot-formed part manufacturing apparatus according to an embodiment of the present invention;
FIG. 2 is a schematic flow chart of a method for preparing a thermoformed part according to an embodiment of the present invention.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
First, an embodiment of the present invention provides a device for preparing a thermoformed part.
Fig. 1 is a schematic structural diagram of a device for preparing a thermoformed part according to an embodiment of the present invention, and referring to fig. 1, the device includes a second mold 2 and a first mold 1, wherein the second mold 2 is fixedly disposed, the second mold 2 is provided with a plurality of through second channels 7 at intervals along a horizontal direction, a top surface of the second mold 2 is provided with a second groove 9, the first mold 1 is disposed right above the second mold 2 in an openable manner, the second mold 1 is provided with a plurality of through first channels 6 at intervals along the horizontal direction, a bottom surface of the first mold 1 is provided with a first groove 8, the first groove 8 and the second groove 9 are disposed correspondingly, and the first groove 8 and the corresponding second groove 9 are disposed oppositely.
Referring to fig. 1, in the embodiment of the present invention, the second mold 2 may be fixedly disposed on the rack 4, the first mold 1 may be fixedly disposed on the transmission table 3, the opening and closing actions of the first mold 1 and the second mold 2 may be realized by operating the transmission table 3, the steel plate 5 is disposed between the first mold 1 and the second mold 2, and the hot stamping of the steel plate 5 may be realized by opening and closing the first mold 1 and the second mold 2.
Further, referring to fig. 1, in the embodiment of the present invention, the horizontal ends of the second channel 7 are respectively provided with a second inlet 12 and a second outlet 13, and the horizontal ends of the first channel 6 are respectively provided with a first inlet 10 and a first outlet 11, so that the cooling liquid 14 can flow through the second channel 7 and the first channel 6 through the inlets and the outlets.
Referring to fig. 1, in the embodiment of the present invention, the top surface of the second mold 2 is provided with a plurality of second grooves 9, and correspondingly, the bottom surface of the first mold 1 is provided with a plurality of first grooves 8 corresponding to the second grooves 9.
In the embodiment of the invention, the first grooves 8 and the second grooves 9 form a forming unit, the forming unit corresponds to the areas 15 to be connected of the steel plates 5 one by one, and the steel plates 5 are subsequently mechanically connected with other materials in the areas 15 to be connected, namely N areas 15 to be connected are arranged on one steel plate 5, and N forming units are correspondingly arranged.
In addition, in the embodiment of the present invention, the corresponding forming units corresponding to the to-be-connected region 15 with a short distance may be combined.
In the embodiment of the present invention, the shape and size of the first groove 8 and the second groove 9 of each forming unit are the same, specifically, the shape of the first groove 8 and the second groove 9 may be circular, the diameter of the circular is larger than the diameter of the corresponding connecting area 15 and is not less than 10mm, and the depth of the circular is not less than 1 mm.
Specifically, in the embodiment of the invention, the first die 1 and the second die 2 are both flat dies made of die steel, the rack 4 and the transmission table 3 are mounted on a 300-ton thermoforming press, the first channel 6 and the second channel 7 are respectively 10 pipes with the diameter of 14mm, the number of the pipes is 10, the distances between the first channel 6 and the second channel 7 and the molded surfaces of the first die 1 and the second die 2 are 10mm, the first groove 8 and the second groove 9 are both circular with the diameter of 30mm, and the depth of the grooves is 2 mm.
Based on the preparation device, the embodiment of the invention also provides a preparation method of the hot forming part.
Fig. 2 is a schematic flow chart of a method for manufacturing a thermoformed part according to an embodiment of the present invention, and in conjunction with fig. 2, the method includes:
s1: providing a cooling liquid 14, and enabling the cooling liquid 14 to flow in the first channel 6 and the second channel 7;
s2: operating the preparation device to enable the first die 1 and the second die 2 to be in an opening state;
s3: providing a steel plate 5 heated to be above an austenitizing temperature, and placing the steel plate 5 on the top surface of the second die 2, wherein the steel plate 5 is a to-be-connected area 15 of the steel plate 5 at the positions corresponding to the first groove 8 and the second groove 9;
s4: operating the preparation device to make the first mold 1 and the second mold 2 in a closed state;
s5: operating the preparation device to keep the first die 1 and the second die 2 in a closed state until the region of the steel plate 5 except the region 15 to be connected is cooled to be below the Ms temperature, and finishing the steel plate quenching process;
s6: the manufacturing apparatus is operated to open the first die 1 and the second die 2 and take out the part formed by hot stamping the steel plate 5.
If the surface of the steel sheet 5 has no plating layer, the hot stamped part is subjected to shot blasting to improve the oxidation resistance and rust prevention, and if the surface of the steel sheet 5 has a plating layer, the hot stamped part is not subjected to shot blasting, and the plating layer may be an AlSi plating layer or a GI plating layer.
The specific application is as follows:
the steel plate 5 can be hot forming steel 22MnB5 with the thickness of 1.0mm, the tensile strength of an original plate (before quenching) is 580MPa, no coating is arranged on the surface, the steel plate can be heated to 930 ℃ in a heating furnace, and the temperature is kept for 300s, so that the aim of heating the steel plate 5 to be above the austenitizing temperature is fulfilled.
In addition, the steel plate 5 in this application has a region to be connected 15. And the cooling liquid 14 is water, the flow velocity of which in the first channel 6 and the second channel 7 is 0.5 m/s.
The parts prepared by the preparation method are subjected to shot blasting treatment and then subjected to various tests: the tensile strength of other areas of the part except the area to be connected 15 is 1530MPa, the structure is a martensite structure, and the microhardness is about 500 HV; the structure of the to-be-connected region 15 of the part is mainly ferrite and pearlite, contains a small amount of bainite, and has the microhardness of about 250 HV.
The connection area 15 and the 2.0mm aluminum alloy 6111 are subjected to self-piercing riveting SPR successfully, the joint shear strength is 8.5kN, the connection area 15 and the 2.0mm aluminum alloy 6111 are subjected to hot-melting self-tapping FDS testing, and the rivet successfully pierces the connection area 15 and the aluminum alloy under the condition of no hole, so that the validity of the scheme is verified.
In summary, according to the hot-formed part manufacturing apparatus and the hot-formed part manufactured by the manufacturing method disclosed in the embodiments of the present invention, the structure of the region to be connected of the steel plate is mainly one or more of ferrite, pearlite, bainite, and the like, and the structure of the steel plate outside the region to be connected is mainly martensite, the hardness of the region to be connected is significantly lower than that of other regions of the part, and as the hardness of the region to be connected is reduced, the subsequent position is convenient for mechanical connection such as self-piercing riveting, hot-melting self-tapping, and the like with other materials, so that the positioning is convenient, and the joint strength can be ensured.
The above-mentioned embodiments are only for convenience of description of the invention, and are not intended to limit the invention in any way, and those skilled in the art will recognize that the invention can be practiced without departing from the spirit and scope of the invention.
Claims (10)
1. A hot formed part preparation apparatus, comprising:
the second die (2) is fixedly arranged, a plurality of through second channels (7) are arranged at intervals in the horizontal direction of the second die (2), and a second groove (9) is formed in the top surface of the second die (2);
first mould (1), first mould (1) can set up with opening and shutting second mould (2) directly over, first mould (1) is provided with a plurality of first passageways (6) that link up to the interval along the level, the bottom surface of first mould (1) is provided with first recess (8), first recess (8) with second recess (9) correspond the setting, first recess (8) and corresponding second recess (9) set up relatively.
2. A device for preparing thermoformed parts according to claim 1, characterized in that the top face of the second mould (2) is provided with a plurality of said second recesses (9), and correspondingly the bottom face of the first mould (1) is provided with a plurality of said first recesses (8) corresponding to said second recesses (9).
3. A device for preparing thermoformed parts according to claim 1, wherein the first recess (8) and the second recess (9) are both circular in shape, the first recess (8) and the second recess (9) having a depth of 1mm or more.
4. The device for preparing hot-formed parts according to claim 1, characterized in that the first die (1) and the second die (2) are both made of die steel.
5. A method of making a thermoformed part, said method comprising:
providing a cooling liquid (14), and enabling the cooling liquid (14) to flow in the first channel (6) and the second channel (7);
operating the manufacturing apparatus according to any one of claims 1 to 4, such that the first mold (1) and the second mold (2) are in an open state;
providing a steel plate (5) heated to above austenitizing temperature, and placing the steel plate (5) on the top surface of the second mold (2), wherein the steel plate (5) is a region (15) to be connected of the steel plate (5) corresponding to the first groove (8) and the second groove (9)
Operating the preparation device to bring the first mould (1) and the second mould (2) into a closed state;
operating the preparation device to keep the first die (1) and the second die (2) in a closed state until the region of the steel plate outside the region to be connected is cooled to be below the Ms temperature, and finishing the steel plate quenching process;
and operating the preparation device, opening the first die (1) and the second die (2), and taking out the part formed by hot stamping the steel plate (5).
6. A method for producing a hot-formed part according to claim 5, characterized in that the steel sheet (5) is a hot-formed steel sheet.
7. A method for producing a hot-formed part according to claim 5, wherein the taking out of the part formed by hot stamping the steel plate (5) further comprises:
and (4) carrying out shot blasting on the hot stamped part.
8. A method for producing a hot-formed part according to claim 5, characterized in that the surface of the steel sheet (5) has a coating.
9. A method of producing a thermoformed part according to claim 8 wherein said coating is an AlSi coating or a GI coating.
10. A method of making a thermoformed part according to claim 5 wherein said coolant is water.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010210575.1A CN111390033A (en) | 2020-03-24 | 2020-03-24 | Device and method for preparing hot-formed part |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010210575.1A CN111390033A (en) | 2020-03-24 | 2020-03-24 | Device and method for preparing hot-formed part |
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| Publication Number | Publication Date |
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| CN111390033A true CN111390033A (en) | 2020-07-10 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010210575.1A Pending CN111390033A (en) | 2020-03-24 | 2020-03-24 | Device and method for preparing hot-formed part |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003328031A (en) * | 2002-05-13 | 2003-11-19 | Nissan Motor Co Ltd | Method for quenching pressed parts, quenching device, and pressed parts |
| KR20150043938A (en) * | 2013-10-15 | 2015-04-23 | (주)일지테크 | Hot stamping mold for hot stamping strip masking |
| CN104889218A (en) * | 2015-06-24 | 2015-09-09 | 武汉理工大学 | Method and die for obtaining variable-intensity hot stamping part |
| CN205056924U (en) * | 2015-09-29 | 2016-03-02 | 苏州飞拓精密模具有限公司 | Curved surface frame mould riveted structure |
| CN107000018A (en) * | 2014-06-25 | 2017-08-01 | 蒂森克虏伯钢铁欧洲股份公司 | Method and shaping jig and corresponding workpiece for thermoforming |
| CN108787904A (en) * | 2018-06-07 | 2018-11-13 | 武汉理工大学 | A kind of punching press of patch reinforcement structure and riveting integrated technique and mold |
| CN210059556U (en) * | 2019-06-14 | 2020-02-14 | 江苏财经职业技术学院 | Floating convex die hot forming die for steel patch plate |
-
2020
- 2020-03-24 CN CN202010210575.1A patent/CN111390033A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2003328031A (en) * | 2002-05-13 | 2003-11-19 | Nissan Motor Co Ltd | Method for quenching pressed parts, quenching device, and pressed parts |
| KR20150043938A (en) * | 2013-10-15 | 2015-04-23 | (주)일지테크 | Hot stamping mold for hot stamping strip masking |
| CN107000018A (en) * | 2014-06-25 | 2017-08-01 | 蒂森克虏伯钢铁欧洲股份公司 | Method and shaping jig and corresponding workpiece for thermoforming |
| CN104889218A (en) * | 2015-06-24 | 2015-09-09 | 武汉理工大学 | Method and die for obtaining variable-intensity hot stamping part |
| CN205056924U (en) * | 2015-09-29 | 2016-03-02 | 苏州飞拓精密模具有限公司 | Curved surface frame mould riveted structure |
| CN108787904A (en) * | 2018-06-07 | 2018-11-13 | 武汉理工大学 | A kind of punching press of patch reinforcement structure and riveting integrated technique and mold |
| CN210059556U (en) * | 2019-06-14 | 2020-02-14 | 江苏财经职业技术学院 | Floating convex die hot forming die for steel patch plate |
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Application publication date: 20200710 |
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