KR20170108477A - The Trimming Method of Super High Tensile Strength Steel Plate Using The Coining Method - Google Patents

The Trimming Method of Super High Tensile Strength Steel Plate Using The Coining Method Download PDF

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Publication number
KR20170108477A
KR20170108477A KR1020160032440A KR20160032440A KR20170108477A KR 20170108477 A KR20170108477 A KR 20170108477A KR 1020160032440 A KR1020160032440 A KR 1020160032440A KR 20160032440 A KR20160032440 A KR 20160032440A KR 20170108477 A KR20170108477 A KR 20170108477A
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KR
South Korea
Prior art keywords
coining
steel plate
steel sheet
trimming
forming
Prior art date
Application number
KR1020160032440A
Other languages
Korean (ko)
Inventor
박장우
Original Assignee
현대자동차주식회사
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Publication date
Application filed by 현대자동차주식회사 filed Critical 현대자동차주식회사
Priority to KR1020160032440A priority Critical patent/KR20170108477A/en
Publication of KR20170108477A publication Critical patent/KR20170108477A/en

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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D28/00Shaping by press-cutting; Perforating
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D22/00Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/02Stamping using rigid devices or tools
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D22/00Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/02Stamping using rigid devices or tools
    • B21D22/022Stamping using rigid devices or tools by heating the blank or stamping associated with heat treatment
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D22/00Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/02Stamping using rigid devices or tools
    • B21D22/04Stamping using rigid devices or tools for dimpling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D28/00Shaping by press-cutting; Perforating
    • B21D28/02Punching blanks or articles with or without obtaining scrap; Notching
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D35/00Combined processes according to or processes combined with methods covered by groups B21D1/00 - B21D31/00
    • B21D35/002Processes combined with methods covered by groups B21D1/00 - B21D31/00
    • B21D35/005Processes combined with methods covered by groups B21D1/00 - B21D31/00 characterized by the material of the blank or the workpiece
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D37/00Tools as parts of machines covered by this subclass
    • B21D37/16Heating or cooling
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D53/00Making other particular articles
    • B21D53/88Making other particular articles other parts for vehicles, e.g. cowlings, mudguards
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D24/00Special deep-drawing arrangements in, or in connection with, presses
    • B21D24/16Additional equipment in association with the tools, e.g. for shearing, for trimming

Abstract

The present invention relates to a trimming method for an ultra high tensile steel plate, and more particularly, to a super high tensile strength steel plate trimming method using coining that enables hard trimming by pressing by coining the super high tensile steel plate with a forming step.
According to an aspect of the present invention, there is provided an ultra high strength steel plate trimming method using coining wherein a hot stamping steel sheet is simultaneously subjected to a forming step and a coining step.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a trimming method for super high tensile strength steel plate using coining,
The present invention relates to a trimming method for an ultra high tensile steel plate, and more particularly, to a super high tensile steel plate trimming method using coining that enables hard trimming by pressing by coining the super high tensile steel plate with a forming step.
Recently, environmental problems are emerging all over the world, and in order to cope with such problems in the whole industry, a method of saving fuel is being sought. In order to achieve fuel savings, the solution proposed in the field of automobile industry is to improve the efficiency of the automobile engine and reduce the weight of the automobile. If the vehicle is lightened, it can be a good measure to increase the fuel efficiency of the car. However, if the weight of the vehicle is reduced, the strength and durability required of the vehicle can not be satisfied. Therefore, solving this problem is becoming a major goal of the automobile industry.
Accordingly, the automobile industry is developing a variety of eco-friendly vehicles aiming to reduce carbon dioxide emissions to 95% of the current level, or 27%, by 2021. In addition, to meet the US Corporate Average Fuel Economy (CAFE) of 54.5 mpg (23.2 km / l) in 2025, automakers are committed to developing downsizing and fuel efficiency technologies.
In recent years, the automobile industry has been trying to achieve the goal of securing the passengers' stability at the time of collision, lightening of the vehicle for the purpose of preventing environmental pollution and fuel economy of the vehicle. As a method to solve this problem, hot stamping steel sheet is applied to major collision parts of vehicle, and its application is expected to increase in the future.
In the case of the hot stamping steel sheet of the prior art, a steel sheet in the form of a coil is blanked, and then the blanked material is heated and press-formed and cooled. The blanked material was completely transformed into austenite structure through high-temperature heating, followed by press forming using a metal mold and rapid cooling to produce a martensite structure to produce an ultra high tensile steel sheet. However, there is a problem in that, when cutting the ultra-high strength steel sheet due to the high strength obtained after forming and cooling the hot stamped steel sheet, the conventional press can not be cut. Therefore, in the case of the ultra-high tensile steel sheet produced according to the prior art, the laser trimming technique was used for cutting. However, laser trimming introduces low productivity and costly laser trimming equipment, which is costly to maintain. Therefore, there is a problem that the hot stamping steel sheet is inefficient compared to the conventional steel sheet in terms of cost and productivity. Furthermore, due to the characteristics of the laser, parts corrosion may occur due to the welding chips and spatter generated after the trim process of the parts, and the steel sheet is softened by the heat generated by the laser.
The present invention has been conceived to solve the problems of the above-described prior art, and it is an object of the present invention to provide a super high tensile strength steel sheet which can reduce the production cost of super high tensile strength steel sheet, increase production efficiency, prevent corrosion, The purpose of this invention is to provide a method of plate trim.
The technical objects to be achieved by the present invention are not limited to the technical matters mentioned above, and other technical subjects which are not mentioned can be clearly understood by those skilled in the art from the description of the present invention .
According to an aspect of the present invention, there is provided an ultra high strength steel plate trimming method using coining wherein a forming step and a coining step are simultaneously performed on a hot stamping steel sheet.
In the present invention, it is preferable that the coining bush used in the coining step is mounted on the flange end portion.
In the present invention, it is preferable that the coining bush is mounted on the upper mold and the lower mold used in the molding step.
In the present invention, it is preferable that the coring bushes have the same materials as those used for the upper mold and the lower mold used in the molding step.
In the present invention, it is preferable that the coining bush is detachable.
In the present invention, when the thickness of the hot stamping steel sheet is more than 0 mm but not more than 1.5 mm, it is preferable that the coining bushes protrude from the mold to a height of 0.5 mm each.
In the present invention, when the thickness of the hot stamping steel sheet is more than 1.5 mm, it is preferable that the coining bush is protruded to the outside of the mold at a height of 30% of the thickness of the hot stamping steel sheet.
In the present invention, it is preferable that the hot stamping steel sheet is hard-trimmed by a press after the forming step and the coining step are simultaneously performed.
In the present invention, before the hot stamping steel sheet is simultaneously subjected to the forming step and the coining step, a material blanking step of blanking the coil-shaped steel sheet; And a heating step of heating the blanked material.
The super high tensile steel plate trimming method using coining according to the present invention can reduce the production cost of super high tensile strength steel plate and increase the production efficiency as well as the super high tensile strength steel plate by using coining which prevents corrosion and prevents softening of steel sheet There is an effect of providing a method.
1 is a photographic view of a laser trimming apparatus according to the prior art;
Figure 2 is a photograph of a scattered welding chip generated by laser trimming in accordance with the prior art.
3 is a photograph showing corrosion of a super high tensile strength steel plate caused by a welding chip or a spatter generated during a laser trimming process according to the related art.
FIG. 4 is a block diagram of a laser trimming method according to the prior art; FIG.
FIG. 5 is a view showing a step-by-step construction view of a method of trimming high strength steel plate using coining according to an embodiment of the present invention.
6 is a schematic view of a front section of a general steel plate by a hard trim according to the prior art.
7 is a schematic view of a section of a super high tensile steel plate front section by a hard trim according to an embodiment of the present invention.
Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. Prior to this, terms and words used in the present specification and claims should not be construed as limited to ordinary or dictionary terms, and the inventor should appropriately interpret the concepts of the terms appropriately It should be interpreted in accordance with the meaning and concept consistent with the technical idea of the present invention based on the principle that it can be defined. Therefore, the embodiments described in this specification and the configurations shown in the drawings are merely the most preferred embodiments of the present invention and do not represent all the technical ideas of the present invention. Therefore, It is to be understood that equivalents and modifications are possible.
The present invention relates to an ultra high strength steel plate trimming method using coining. In order to secure the light weight and stability of the vehicle, it has been increasingly applied to the super high tensile steel sheet for the vehicle. Generally, the ultra-high tensile steel sheet is produced by blanking a coil-shaped steel sheet, then heating the blanked material, and press-forming and cooling the hot-stamped steel sheet 20. This is because the steel sheet is heated and molded at a high temperature to facilitate molding, and the hot stamping steel sheet 20 is rapidly cooled in the metal mold, so that not only the super strength is increased but also the residual stress due to the phase transformation disappears and the dimensional accuracy of the ultra high tensile steel sheet is improved.
However, it was impossible to trim (hard trim) an ordinary press due to a high strength of 120K or more. 1 is a photograph of a laser trimming apparatus 17 according to the prior art. In the prior art, it is impossible to hard trim an ultra high strength steel plate, and a laser trimming process or the like is used as shown in FIG. The laser trimming is not only low in production, but also requires a high process ratio, that is, high equipment introduction cost and high maintenance cost.
2 is a photographic view of a scattered welding chip generated by laser trimming according to the prior art. 3 is a photographic view showing corrosion of a super high tensile steel plate caused by a welding chip or a spatter generated during a laser trimming process according to the related art. In the laser trimming, due to the characteristics of the laser, welding chip and spatter generated as shown in FIG. 2 are generated after the component is trimmed. Also, as shown in FIG. 3, component corrosion may occur, do.
In order to solve the above problems, the present invention provides an ultra high strength steel plate trimming method using coining in which a forming step and a coining step are simultaneously performed on a hot stamped steel sheet 200. The coining bush 107 used in the coining step is preferably mounted on the end of the flange and the coining bush 107 is mounted on the upper die 101 and the lower die 103 used in the forming step. . It is preferable that the coining bush 107 is made of the same material as that of the upper mold 101 and the lower mold 103 used in the molding step and that the coining bush 107 is detachable Do. Further, when the thickness of the hot stamping steel plate 200 is more than 0 mm but not more than 1.5 mm, it is preferable that the coining bosses 107 protrude 0.5 mm from the outside of the metal mold, When the thickness exceeds 1.5 mm, it is preferable that the coining bush 107 is protruded to the outside of the mold at a height of 30% of the thickness of the hot stamping steel plate 200. In addition, the hot stamping steel sheet 200 is hard to be trimmed by a press after the forming step and the coining step are performed simultaneously, and the hot stamping steel sheet 200 is subjected to a forming step and a coining step; A material blanking step of blanking the steel sheet in the form of a coil before being simultaneously performed; And a heating step of heating the blanked material.
FIG. 4 is a step-by-step configuration diagram of a laser trimming method according to the related art. The prior art produces a blank and then transfers the blank to a hydraulic press while heating from room temperature to 950 ° C. Thereafter, the heated blank is formed by a hydraulic press, and the upper mold 11 and the lower mold 13 of the hydraulic press are cooled by the cooling water 15 of the cooling device already installed. Thereafter, the ultra-high strength steel sheet having been subjected to the above-described forming process is taken out, and then cut using a laser trimming device 17. However, as described above, the super high tensile strength steel plate manufactured by the prior art has a problem that it can not be cut by a general press due to high strength, and is cut by the laser trimmer 17 as shown in FIG. SUMMARY OF THE INVENTION Accordingly, the present invention has been made in view of the above problems, and an object of the present invention is to provide an ultra high strength steel plate trimming method using coining that simultaneously performs a forming step and a coining step. FIG. 5 is a step-by-step configuration diagram of a super high strength steel plate trimming method using coining according to an embodiment of the present invention. The present invention produces a blank by blanking a steel sheet in the form of a coil. The blank is then heated to about 950 DEG C while being transferred to a hydraulic press. 4, the blank is formed by a press die having a coring bush 107 mounted on a flange end portion of the upper die 101 and the lower die 103. As shown in FIG. Simultaneously with the above molding step, the distal end of the flange is coined. If coining is performed after the forming step, the strength of the hot stamping steel sheet 200 becomes high, which makes it impossible to perform coining. In the present invention, the above problem is solved by simultaneously performing the forming step and the coining step. In the forming step, the hot stamping steel sheet 200 heated by the coring bush of the metal mold is squeezed. Thereafter, the upper mold 101 and the lower mold 103 of the hydraulic press are cooled by the cooling water 105 of the already installed cooling apparatus. Next, the cooled hot stamping steel sheet 200 is hard-trimmed using a press.
The ultra-high strength steel plate trimming method using coining according to the present invention can be applied to a mold material used in the molding step is SKD11 or other commonly used material and vacuum heat-treated to the mold material. Further, the coining bush 107 applied to the present invention may be the same as the above-described metal material, and the coining bush 107 can be attached to and detached from the upper die 101 and the lower die 103 of the present invention . If the hot stamped steel sheet 200 is 0 to 1.5 mm or less, the coining bush 107 applied to the upper die 101 and the coining boss 107 applied to the lower die 103 are pressed against the die It is preferable that they protrude to the outside at a height of 0.5 mm each. When the hot stamping steel sheet 200 is more than 1.5 mm, it is preferable that the hot stamping steel sheet 200 is protruded by 30% of the thickness of the hot stamping steel sheet 200.
6 is a structural view of a front section of a general steel plate by a hard trim according to the prior art. When a steel sheet is sheared by using a general press of the prior art, it can be seen that a burr is generated in the lower part of the front section as shown in FIG. 7 is a structural view of a section of a super high tensile strength steel plate with a hard trim according to an embodiment of the present invention. The coining step is carried out simultaneously with the shaping step to form the indentation at the flange end of the ultra high strength steel plate. When a hard trim is performed by using the press, it can be confirmed that no burr occurs as shown in FIG.
The present invention is advantageous for producing a hot stamped steel sheet and parts using the hot stamped steel sheet 200 because the forming step using the press of the hot stamped steel sheet 200 and the coining step are simultaneously performed and cut through a hard trim using a press instead of laser trimming As compared with laser trimming of the prior art, the present invention is advantageous in that the cycle time is increased by 500% and the productivity is improved by using the hard trim which is excellent in the production efficiency and the production speed, . Furthermore, when the laser beam is trimmed, it is possible to prevent corrosion of parts due to scattered welding chips and spatter.
Although the present invention has been described in connection with the specific embodiments of the present invention, it is to be understood that the present invention is not limited thereto. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention as defined by the appended claims and their equivalents. Various modifications and variations are possible.
11: Prior art mold
13: Prior art lower mold
15: Prior art cooling water
17: Laser trimming device
20: hot stamping steel plate
101: Upper mold of the present invention
103: Lower mold of the present invention
105: Cooling water of the present invention
107: Coining Bush
200: Hot stamping steel plate

Claims (9)

  1. A method of super-high strength steel plate trimming using coining wherein a forming step and a coining step are simultaneously performed on a hot stamping steel sheet.
  2. The method according to claim 1,
    Wherein the coining bush used in the coining step is mounted on the end of the flange.
  3. 3. The method of claim 2,
    Wherein the coining bush is mounted on a top die and a bottom die used in the forming step.
  4. The method of claim 3,
    Wherein the coining bush has the same material applied to the upper die and the lower die used in the forming step.
  5. The method of claim 3,
    Wherein the coining bushes are detachable and attachable to each other.
  6. The method of claim 3,
    Wherein when the thickness of the hot stamped steel sheet is greater than 0 mm but not more than 1.5 mm, the coining bushes are each protruded to a height of 0.5 mm from the outside of the mold.
  7. The method of claim 3,
    Wherein when the thickness of the hot stamping steel plate exceeds 1.5 mm, the coining bush is protruded to the outside of the mold to a height of 30% of the thickness of the hot stamping steel plate.
  8. The method according to claim 1,
    Wherein the hot stamping steel plate is hard-trimmed by a press after the forming step and the coining step are performed at the same time.
  9. 9. The method of claim 8,
    Before the hot stamping steel sheet is simultaneously subjected to the forming step and the coining step,
    A blanking step of blanking the coil-shaped steel sheet; And
    Further comprising a heating step of heating the blanked material. ≪ Desc / Clms Page number 19 >
KR1020160032440A 2016-03-18 2016-03-18 The Trimming Method of Super High Tensile Strength Steel Plate Using The Coining Method KR20170108477A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
KR1020160032440A KR20170108477A (en) 2016-03-18 2016-03-18 The Trimming Method of Super High Tensile Strength Steel Plate Using The Coining Method

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
KR1020160032440A KR20170108477A (en) 2016-03-18 2016-03-18 The Trimming Method of Super High Tensile Strength Steel Plate Using The Coining Method
US15/211,203 US20170266711A1 (en) 2016-03-18 2016-07-15 Method of trimming ultra high strength hot stamping steel sheet using coining
CN201610600325.2A CN107199277A (en) 2016-03-18 2016-07-27 The method for carrying out trimming to superhigh intensity drop stamping steel plate using molding
DE102016114041.4A DE102016114041A1 (en) 2016-03-18 2016-07-29 Method of trimming ultra-high strength hot stamping steel sheet using embossing

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Publication Number Publication Date
KR20170108477A true KR20170108477A (en) 2017-09-27

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US (1) US20170266711A1 (en)
KR (1) KR20170108477A (en)
CN (1) CN107199277A (en)
DE (1) DE102016114041A1 (en)

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DE102016013879A1 (en) * 2016-11-19 2018-04-12 Audi Ag Method and production of a hot-formed and press-hardened vehicle body component

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US3194047A (en) * 1962-04-24 1965-07-13 Budd Co Method of making a metal sandwich structure panel
CN101486061B (en) * 2009-02-24 2010-08-11 山东大学 Thermoforming, hole-punching and edge-cutting integrated technique and mold of high-duty steel part
CN101486062B (en) * 2009-02-24 2010-12-29 山东大学 Thermoforming and edge-cutting integrated technique and mold of high-duty steel part
CN101972814A (en) * 2010-10-25 2011-02-16 机械科学研究总院先进制造技术研究中心 Ultra-high strength steel hot-stamping die for car door anticollision beam
JP2013094793A (en) * 2011-10-28 2013-05-20 Toyota Motor Corp Hot press forming method, formed object by hot press forming, as well as die for hot press forming
KR101454793B1 (en) * 2012-12-13 2014-10-27 부산대학교 산학협력단 Two step shearing method of hot-stamped ultra-high-strength material for preventing damage of press cutting mold
CN103934360A (en) * 2014-04-25 2014-07-23 吉林大学 Hot stamping and warm blanking composite forming technology and mould for ultrahigh-strength steel
KR102013596B1 (en) 2014-09-16 2019-08-23 한온시스템 주식회사 Oil separator for scroll compressor

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DE102016114041A1 (en) 2017-09-21
CN107199277A (en) 2017-09-26

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