Method for producing hot-pressed member

• US 10,316,381 B2
• Filed: 12/02/2013
• Issued: 06/11/2019
• Est. Priority Date: 10/28/2009
• Status: Active Grant

• Current Assignee: JFE Steel Corporation (JFE Holdings Incorporated)
• Original Assignee: JFE Steel Corporation (JFE Holdings Incorporated)
• Inventors: Nakamaru, Hiroki, Nakajima, Seiji, Miyoshi, Tatsuya, Masuoka, Hiroyuki, Ootsuka, Shinji
• Primary Examiner(s): La Villa, Michael E.
• Application Number:
  US14/094,003
• Publication Number:
  US 20140216611A1
• Time in Patent Office: 2,017 Days
• CPC Class Codes: B21D 22/00 Shaping without cutting, by stamping, spinning, or deep-drawing otherwise than using rigid devices or tools or yieldable or resilient pads B21D26/00
• CPC Class Codes: B21D 22/20 Deep-drawing special deep-drawing arrangements in, or in connection with, presses B21D24/00
• CPC Class Codes: B21D 22/206 articles from a strip in several steps, the articles being coherent with the strip during the operation
• CPC Class Codes: B21D 22/208 by heating the blank or deep-drawing associated with heat treatment C21D takes precedence
• CPC Class Codes: B32B 15/01 all layers being exclusively metallic making layered metal workpieces by pressure cladding B23K20/22; making coatings with a metallic material characterised by its composition C23C30/00
• CPC Class Codes: B32B 15/013 one layer being formed of an iron alloy or steel, another layer being formed of a metal other than iron or aluminium
• CPC Class Codes: B32B 15/015 the said other metal being copper or nickel or an alloy thereof
• CPC Class Codes: B32B 15/04 comprising metal as the main or only constituent of a layer, which is next to another layer of the same or of a different material next to a bituminous or tarry layer B32B11/08; next to a water-setting substance layer B32B13/06; next to a glass layer B32B17/061; next to a cellulosic plastic layer B32B23/042
• CPC Class Codes: B32B 15/043 of metal B32B15/01 takes precedence
• CPC Class Codes: B32B 15/18 comprising iron or steel B32B15/011, B32B15/012 and B32B15/013 take precedence
• CPC Class Codes: C21D 1/673 for die quenching
• CPC Class Codes: C21D 2251/02 Clad material
• CPC Class Codes: C21D 8/005 of ferrous alloys C21D8/02 - C21D8/12 take precedence
• CPC Class Codes: C21D 8/0205 of ferrous alloys
• CPC Class Codes: C21D 8/0247 characterised by the heat treatment
• CPC Class Codes: C21D 8/0457 with diffusion of elements, e.g. decarburising, nitriding
• CPC Class Codes: C22C 18/00 Alloys based on zinc
• CPC Class Codes: C22C 38/001 containing N
• CPC Class Codes: C22C 38/002 containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
• CPC Class Codes: C22C 38/02 containing silicon
• CPC Class Codes: C22C 38/04 : containing manganese
• CPC Class Codes: C22C 38/06 : containing aluminium
• CPC Class Codes: C22C 38/14 : containing titanium or zirconium
• CPC Class Codes: C22C 38/18 : containing chromium
• CPC Class Codes: C22C 38/28 : with titanium or zirconium
• CPC Class Codes: C22C 38/32 : with boron
• CPC Class Codes: C22C 38/34 : with more than 1.5% by weight of silicon
• CPC Class Codes: C22C 38/38 : with more than 1.5% by weight of manganese
• CPC Class Codes: C22C 38/60 : containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur
• CPC Class Codes: C23C 10/28 : using solids, e.g. powders, pastes
• CPC Class Codes: C23C 10/60 : After-treatment
• CPC Class Codes: C23C 2/06 : Zinc or cadmium or alloys based thereon
• CPC Class Codes: C23C 26/00 : Coating not provided for in groups C23C2/00 - C23C24/00
• CPC Class Codes: C23C 28/321 : with at least one metal alloy layer
• CPC Class Codes: C23C 28/322 : only coatings of metal elements only
• CPC Class Codes: C23C 28/325 : with layers graded in composition or in physical properties
• CPC Class Codes: C23C 28/345 : with at least one oxide layer
• CPC Class Codes: C23C 30/005 : on hard metal substrates
• CPC Class Codes: C25D 3/562 : containing more than 50% by weight of iron or nickel or cobalt
• CPC Class Codes: C25D 3/565 : containing more than 50% by weight of zinc
• CPC Class Codes: C25D 5/48 : After-treatment of electroplated surfaces
• CPC Class Codes: C25D 5/50 : by heat-treatment
• CPC Class Codes: Y10T 428/12486 : Laterally noncoextensive components [e.g., embedded, etc.]
• CPC Class Codes: Y10T 428/1259 : Oxide
• CPC Class Codes: Y10T 428/12611 : Oxide-containing component
• CPC Class Codes: Y10T 428/12618 : Plural oxides
• CPC Class Codes: Y10T 428/1266 : O, S, or organic compound in metal component
• CPC Class Codes: Y10T 428/12674 : Ge- or Si-base component
• CPC Class Codes: Y10T 428/12757 : Fe
• CPC Class Codes: Y10T 428/12792 : Zn-base component
• CPC Class Codes: Y10T 428/12799 : Next to Fe-base component [e.g., galvanized]
• CPC Class Codes: Y10T 428/12806 : Refractory [Group IVB, VB, or VIB] metal-base component
• CPC Class Codes: Y10T 428/12931 : Co-, Fe-, or Ni-base components, alternative to each other
• CPC Class Codes: Y10T 428/12937 : Co- or Ni-base component next to Fe-base component
• CPC Class Codes: Y10T 428/12944 : Ni-base component
• CPC Class Codes: Y10T 428/12972 : Containing 0.01-1.7% carbon [i.e., steel]
• CPC Class Codes: Y10T 428/12979 : Containing more than 10% nonferrous elements [e.g., high alloy, stainless]
• CPC Class Codes: Y10T 428/2495 : Thickness [relative or absolute]
• CPC Class Codes: Y10T 428/24967 : Absolute thicknesses specified
• CPC Class Codes: Y10T 428/264 : Up to 3 mils
• CPC Class Codes: Y10T 428/265 : 1 mil or less

Abstract

A method is provided for producing a hot-pressed member including heating a Ni-based coated steel sheet, which includes, on a surface thereof, a Zn—Ni alloy coating layer containing 13% by mass or more of Ni, in a temperature region of an Ac3 transformation point to 1200° C.; and then hot-pressing the steel sheet.

Claims

1. A method for producing a hot-pressed member configured to suppress hydrogen entry associated with corrosion, the method comprising:

a single heating step consisting of heating a steel sheet that has been plated, the steel sheet that has been plated having a Zn—

Ni alloy coating layer containing 13% by mass or more of Ni, directly from room temperature to a temperature region of 850°

C. to 1200°

C., thereby forming a Ni-diffusion region in which Ni is present in a solid-solution state over a range of 1 μ

m or more in the depth direction of the steel sheet and an intermetallic compound layer corresponding to a γ

-phase present in a phase equilibrium diagram of Zn—

Ni alloy on the Ni-diffusion region; and

then

a hot-pressing step comprising hot-pressing the coated steel sheet.

3. The method for producing a hot-pressed member according to claim 1 or 2, wherein the coated steel sheet further includes at least one compound layer selected from a Si-containing compound layer, a Ti-containing compound layer, an Al-containing compound layer, and a Zr-containing compound layer, which is provided on the Zn—

Ni alloy coating layer.

4. The method for producing a hot-pressed member according to claim 3, wherein a base steel sheet of the coated steel sheet has a composition containing, by % by mass, C:

0.15 to 0.5%, Si;

0.05 to 2.0%, Mn;

0.5 to 3%, P;

0.1% or less, S;

0.05% or less, Al;

0.1% or less, N;

0.01% or less, and the balance including Fe and unavoidable impurities.

5. The method for producing a hot-pressed member according to claim 4, wherein the base steel sheet of the coated steel sheet further contains, by % by mass, at least one selected from Cr:

0.01 to 1%, Ti;

0.2% or less, and B;

0.0005 to 0.08%.

6. The method for producing a hot-pressed member according to claim 5, wherein the base steel sheet of the coated steel sheet further contains, by % by mass, Sb:

0.003 to 0.03%.

7. The method for producing a hot-pressed member according to claim 4, wherein the base steel sheet of the coated steel sheet further contains, by % by mass, Sb:

0.003 to 0.03%.

8. The method for producing a hot-pressed member according to claim 1 or 2, wherein a base steel sheet of the coated steel sheet has a composition containing, by % by mass, C:

0.15 to 0.5%, Si;

0.05 to 2.0%, Mn;

0.5 to 3%, P;

0.1% or less, S;

0.05% or less, Al;

0.1% or less, N;

0.01% or less, and the balance including Fe and unavoidable impurities.

9. The method for producing a hot-pressed member according to claim 8, wherein the base steel sheet of the coated steel sheet further contains, by % by mass, at least one selected from Cr:

0.01 to 1%, Ti;

0.2% or less, and B;

0.0005 to 0.08%.

10. The method for producing a hot-pressed member according to claim 9, wherein the base steel sheet of the coated steel sheet further contains, by % by mass, Sb:

0.003 to 0.03%.

11. The method for producing a hot-pressed member according to claim 8, wherein the base steel sheet of the coated steel sheet further contains, by % by mass, Sb:

0.003 to 0.03%.

2. A method for producing a hot-pressed member comprising heating a coated steel sheet, which includes, on a surface thereof, a Zn—

Ni alloy coating layer containing 13% by mass or more of Ni, in a temperature region of an Ac₃ transformation point to 1200°

C.; and

then hot-pressing the steel sheet, wherein the heating in the temperature range of the Ac₃ transformation point to 1200°

C. is performed at an average heating rate of 85°

C./second or more.