EP3260214A1 - Verfahren zur formung einer metallplatte und formprodukt - Google Patents

Verfahren zur formung einer metallplatte und formprodukt Download PDF

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Publication number
EP3260214A1
EP3260214A1 EP16752596.3A EP16752596A EP3260214A1 EP 3260214 A1 EP3260214 A1 EP 3260214A1 EP 16752596 A EP16752596 A EP 16752596A EP 3260214 A1 EP3260214 A1 EP 3260214A1
Authority
EP
European Patent Office
Prior art keywords
forming
yield strength
metal sheet
reinforcement
fiber reinforced
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Pending
Application number
EP16752596.3A
Other languages
English (en)
French (fr)
Other versions
EP3260214A4 (de
Inventor
Masahiro Saito
Tohru Yoshida
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Nippon Steel Corp
Original Assignee
Nippon Steel and Sumitomo Metal Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Nippon Steel and Sumitomo Metal Corp filed Critical Nippon Steel and Sumitomo Metal Corp
Publication of EP3260214A1 publication Critical patent/EP3260214A1/de
Publication of EP3260214A4 publication Critical patent/EP3260214A4/de
Pending legal-status Critical Current

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Classifications

    • 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
    • B21D22/20Deep-drawing
    • B21D22/201Work-pieces; preparation of the work-pieces, e.g. lubricating, coating
    • 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
    • B21D22/20Deep-drawing
    • 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
    • B21D22/20Deep-drawing
    • B21D22/203Deep-drawing of compound articles
    • 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
    • B21D35/007Layered blanks

Definitions

  • the present invention relates to a method of forming a metal sheet in which no breakage occurs during forming such as by drawing, stretch flanging, bending, and stretch forming and a formed part formed by that method of forming.
  • FIG. 1 shows a mode of breakage at a shoulder part of a punch when drawing a metal sheet.
  • the blank material 1 of the metal sheet is drawn by pressing a flange part 1' of a blank material 1 in a die 2 by a blank holder 4 while pressing it by a punch 3.
  • Drawing proceeds by a balance of a breaking yield strength of the blank material 1 at the shoulder part 3' of the punch 3 and the pulling force acting on the flange part 1' of the blank material 1.
  • PLT 1 proposes a method of press-forming a blank material during which a location of the blank material where a reduction in thickness is anticipated is provided with two or more weld beads and then the press-forming operation is performed.
  • PLT 2 proposes a tailored blank material for press-forming use excellent in deep drawability obtained by welding a high strength steel sheet having a 15% or more lower strength and sheet thickness than the material at a center part or a 5% or more better ductility than the material of the center part with another steel sheet forming the center part over the entire circumference of a drawn flange part at a part imparting a wrinkle suppressing force at the time of forming at the outside the part becoming the final product after deep drawing.
  • improvement of the forming process and improvement of the material of the metal sheet may be considered.
  • the method of division of the dies and increase of the number of pressing processes may be considered, but with these methods, a rise in the forming costs and fall in the productivity are unavoidable.
  • PLTs 1 and 2 disclose improvement of the material of the high strength steel sheet by changing (strengthening) the material by partial hardening or bonding with different materials.
  • a rise in the forming costs and fall in the productivity are unavoidable.
  • the present invention has as its problem preventing a metal sheet from breaking when forming a metal sheet without changing the material of the metal sheet and the forming process and has as its object the provision of a method of forming solving that problem and a formed part formed by that method of forming.
  • the present invention was made based on the above discovery and has as its gist the following:
  • the present invention when forming a metal sheet, it is possible to raise the breaking yield strength of a portion where breaking yield strength is required, improve the formability of the metal sheet, and prevent breakage during drawing without changing the material of the metal sheet and the forming process.
  • the method of forming a metal sheet of the present invention is a method of forming a metal sheet comprising drawing a sheet with a reinforcement bonded in advance to a portion where breaking yield strength is required (below, referred to as "a portion where breakage is a concern").
  • the formed part of the present invention is characterized by being formed by the method of forming of the present invention.
  • FIG. 2 shows as one example of the present invention a mode of drawing a high strength steel sheet wherein a sheet of fiber reinforced plastic is bonded with a portion where breaking yield strength is required so as to prevent breakage.
  • a blank material 1 of a high strength steel sheet is drawn by pressing a flange part 1' of the blank material 1 in a die 2 by a blank holder 4 while pressing it by a punch 3. Drawing proceeds by a balance of the breaking yield strength of the blank material 1 at the shoulder part 3' of the punch 3 and the pulling force acting on the flange part 1' of the blank material 1.
  • a reinforcement comprised of a sheet of fiber reinforced plastic 8 is bonded in advance with a portion 7 where breaking yield strength is required and then the drawing operation is performed.
  • FIG. 2 shows a mode of bonding a fiber reinforced plastic sheet 8 so as to surround a bottom part of a drawn part so that during drawing of high strength steel sheet, the fiber reinforced plastic sheet 8 reliably bonds with the portion 7 where breaking yield strength is required and can sufficiently exert the function of improving the breaking yield strength.
  • the mode of bonding the reinforcement to the portion where breaking yield strength is required is not limited to the mode of bonding shown in FIG. 2 .
  • Various modes of bonding can be employed so long as reliably bonding the reinforcement with the portion where breaking yield strength is required. This point will be explained later while showing another bonding mode.
  • the method of forming of the present invention has as its basic idea bonding a reinforcement with a forming material (blank material) before a forming operation so as to raise the formability of the portion with the sheet or patch bonded to it.
  • the method of forming of the present invention basically differs from the above technique of bonding a sheet or patch of fiber reinforced plastic to a formed part after the forming operation so as to improve the mechanical properties or functionality of the formed part or reinforce it.
  • FIGS. 3A and 3B show a mode in drawing high strength steel sheet where a patch of fiber reinforced plastic is bonded with a portion where breaking yield strength is required.
  • FIG. 3A shows a mode where a patch of ring-shaped fiber reinforced plastic is bonded to a ring-shaped portion where breaking yield strength is required, while FIG. 3B shows a cross-section of a formed part obtained by drawing the blank material shown in FIG. 3A .
  • a reinforcement comprised of a ring-shaped fiber reinforced plastic sheet 8a is bonded so as to cover a portion where breakage during drawing is a concern, that is, a ring-shaped portion abutting against a shoulder part of the punch and requiring breaking yield strength.
  • FIGS. 4A and 4B show another mode when drawing high strength steel sheet where patches of fiber reinforced plastic are bonded to portions where breaking yield strength is required.
  • FIG. 4A shows a mode where patches of ring-shaped fiber reinforced plastic are bonded to two ring-shaped portions where breaking yield strength is required, while FIG. 4B shows a cross-section of a formed part obtained by drawing the blank material shown in FIG. 4A .
  • ring-shaped fiber reinforced plastic sheet 8b and 8c are bonded so as to cover the portions where breakage during drawing is a concern, that is, the two ring-shaped portions abutting against the shoulder parts of a punch and requiring breaking yield strength.
  • FIGS. 3A and 3B and FIGS. 4A and 4B show the case of drawing a circular blank material axially symmetrically, but the blank material is not limited to a circular blank material. Further, the drawing operation is not limited to drawing axially symmetrically.
  • the breaking yield strength of a portion where breaking yield strength is required (a portion where breakage is a concern) is improved, so the freedom of shape of the blank material, freedom of the forming mode, and freedom of shape of the formed part are greatly expanded.
  • FIGS. 3A and 3B and FIGS. 4A and 4B show the states when bonding reinforcements comprised of ring-shaped sheets of fiber reinforced plastic to portions where breaking yield strength is required.
  • the shape of the reinforcement is not limited to a specific shape and may be suitably set in accordance with the shape, position, etc. of the identified portion where breaking yield strength is required.
  • FIGS. 3A and 3B and FIGS. 4A and 4B show modes of bonding ring-shaped sheets of fiber reinforced plastic to the outsides of portions where breaking yield strength is required, but the locations of bonding the reinforcement are not limited to the outsides of the portions where breaking yield strength is required. They may be any of the inside, outside, and two sides of the portion where breaking yield strength is required. The locations of bonding the reinforcement may be suitably set according to the shapes, positions, etc. of the portions where breaking yield strength is required.
  • a reinforcement when bonding a reinforcement to a portion where breaking yield strength is required, it may also be bonded divided into suitable sections.
  • FIG. 5 shows a mode of bonding a reinforcement comprised of divided sections of ring-shaped fiber reinforced plastic to a ring-shaped portion where breaking yield strength is required.
  • the ring-shaped fiber reinforced plastic is divided into four sections.
  • the sections of fiber reinforced plastic 8a' are bonded arranged in a ring shape.
  • the mode of division may be suitably determined according to the shape, position, etc. of the portion where the specified breaking yield strength is required.
  • FIGS. 6 to 9 show portions where breakage is a concern in various forming operations.
  • FIG. 6 shows deep drawing
  • FIG. 7 shows stretch flanging
  • FIG. 8 shows bending
  • FIG. 9 shows stretch forming. If such general forming operations, a portion where breakage is a concern can be predicted relatively easily.
  • the portion where breakage is a concern is the punch shoulder 61, with stretch flanging, it is the flange end 71, with bending, it is the bent portion 81, and with stretch forming, it is the punch stretching portions 91. Therefore, before forming the metal sheet, it is sufficient to bond a reinforcement and then performing forming so as to cover a position forming that portion at the time of forming.
  • CAE computer aided engineering
  • the reinforcement is not particularly limited in grade so long as one able to bear the stress applied to the portion where breakage during forming is a concern. If considering the strength and ease of handling, a sheet of fiber reinforced plastic or high strength steel foil is preferably used.
  • the fiber reinforced plastic need only be a plastic reinforced by a fiber. It is not limited to any specific fiber or plastic. As a suitable example, carbon fiber reinforced plastic may be mentioned.
  • high strength steel foil steel foil having a tensile strength at ordinary temperature of 600 MPa or more can be illustrated.
  • the fiber reinforced plastic is preferably bonded so that the direction of the fibers runs along the direction in which breaking yield strength is required, specifically, cuts across any crack formed.
  • the reinforcement is designed to improve the breaking yield strength at the portion where breaking yield strength is required, so a required thickness is necessary, but the material is not limited to a specific thickness.
  • the thickness of the reinforcement may be suitably set considering the grade of the blank material, the mode of drawing, the shape of the formed part, etc.
  • the formed part obtained by forming a blank material with a reinforcement bonded to the portion where breaking yield strength is required may, depending on the application, be used after removing the reinforcement or may be used with the reinforcement remaining bonded as it is.
  • the bonding strength when bonding a reinforcement with a portion where breaking yield strength is required may be suitably selected in accordance with the application of the formed part.
  • the method of bonding the reinforcement with a portion where breaking yield strength is required is not particularly limited.
  • an adhesive or resin is preferably used.
  • the types of the adhesive and resin are not particularly limited. It is also possible to consider whether to remove the reinforcement from the formed part or leave it as it is so as to suitably select the adhesive. If the reinforcement is high strength steel foil and the reinforcement does not have to be removed from the formed part, it may be bonded by diffusion bonding.
  • the method of forming of the present invention exhibits its effect without regard to the worked material, that is, the metal sheet, and the content of the forming operation. In particular, it exhibits a large effect in forming high strength steel sheet with a tensile strength of 590 MPa or more - which tends to become low in formability.
  • the conditions in the example are an illustration of the conditions employed for confirming the workability and effect of the present invention.
  • the present invention is not limited to this illustration of conditions.
  • the present invention can employ various conditions so long as not deviating from the gist of the present invention and achieving the object of the present invention.
  • a thickness 1.0 mm, diameter 108 mm blank material (dual phase steel) 112 and a thickness 0.7 mm, diameter 58 mm adhesive sheet (polypropylene resin sheet) 113 and thickness 0.23 mm, diameter 58 mm sheet of carbon fiber reinforced plastic 111 were stacked in that order.
  • the assembly was heated by a hot crimping machine 114 at 180°C for 1 minute, then pressed at 0.049 MPa ( ⁇ 5 tonf/m 2 ) for 1 minute and air-cooled to bond the carbon fiber reinforced plastic 111 with the blank material 112.
  • the blank material 112 with the carbon fiber reinforced plastic 111 bonded to it was drawn using the punch and die used in the comparative example.
  • a thickness 1.0 mm, diameter 108 mm blank material (dual phase steel) was drawn using the following punch and die: Punch shoulder: R5
  • FIG. 12 shows the results of a comparative example of drawing a portion where breaking yield strength is required to which a sheet of fiber reinforced plastic is not bonded, while (b) shows the results of an example of drawing a portion where breaking yield strength is required to which a sheet of fiber reinforced plastic is bonded.
  • the present invention when forming a metal sheet, it is possible to raise the breaking yield strength of a portion where breaking yield strength is required, improve the formability of the metal sheet, and prevent breakage during forming without changing the material of the metal sheet and the forming process.
  • the present invention exhibits its effect regardless of the worked material, that is, the metal sheet, and the content of the forming operation. In particular, it exhibits a great effect for operations on high strength steel sheet where the formability tends to become low like drawing, stretch forming, stretch flanging, and bending.
  • the present invention has high applicability in industries manufacturing metal products.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)
  • Laminated Bodies (AREA)
  • Resistance Welding (AREA)
  • Table Devices Or Equipment (AREA)
  • Forging (AREA)
EP16752596.3A 2015-02-19 2016-02-19 Verfahren zur formung einer metallplatte und formprodukt Pending EP3260214A4 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
JP2015031029 2015-02-19
PCT/JP2016/054936 WO2016133210A1 (ja) 2015-02-19 2016-02-19 金属板の成形方法及び成形品

Publications (2)

Publication Number Publication Date
EP3260214A1 true EP3260214A1 (de) 2017-12-27
EP3260214A4 EP3260214A4 (de) 2018-11-14

Family

ID=56689341

Family Applications (1)

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EP16752596.3A Pending EP3260214A4 (de) 2015-02-19 2016-02-19 Verfahren zur formung einer metallplatte und formprodukt

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Country Link
US (1) US20180021835A1 (de)
EP (1) EP3260214A4 (de)
JP (1) JP6477860B2 (de)
KR (1) KR102017970B1 (de)
CN (1) CN107427888B (de)
BR (1) BR112017017544A2 (de)
CA (1) CA2976626C (de)
MX (1) MX2017010644A (de)
MY (1) MY189189A (de)
RU (1) RU2682736C2 (de)
TW (2) TWI640373B (de)
WO (1) WO2016133210A1 (de)

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JP6583305B2 (ja) * 2017-02-20 2019-10-02 Jfeスチール株式会社 フランジ付き穴形状の成形方法
JP6614183B2 (ja) * 2017-02-27 2019-12-04 トヨタ自動車株式会社 自動車用パネル部材
KR102428824B1 (ko) 2019-12-11 2022-08-02 주식회사 포스코 금속-플라스틱 복합소재 및 이의 제조 방법
CN112605219B (zh) * 2020-11-27 2022-04-01 广州纬华节能设备有限公司 一种双相钢拉伸方法

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Also Published As

Publication number Publication date
JPWO2016133210A1 (ja) 2017-12-07
TW201808486A (zh) 2018-03-16
TW201703896A (zh) 2017-02-01
CA2976626C (en) 2020-01-21
BR112017017544A2 (pt) 2018-04-17
RU2682736C2 (ru) 2019-03-21
WO2016133210A1 (ja) 2016-08-25
MY189189A (en) 2022-01-31
RU2017132459A3 (de) 2019-03-20
JP6477860B2 (ja) 2019-03-06
EP3260214A4 (de) 2018-11-14
TWI640373B (zh) 2018-11-11
US20180021835A1 (en) 2018-01-25
RU2017132459A (ru) 2019-03-20
CA2976626A1 (en) 2016-08-25
KR20170103938A (ko) 2017-09-13
MX2017010644A (es) 2017-11-23
KR102017970B1 (ko) 2019-09-03
CN107427888A (zh) 2017-12-01
CN107427888B (zh) 2021-02-19

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