Method of manufacturing hot press formed part, and hot press formed part

Patent metadata

Field	Value
Publication number	US-2016208355-A1
Application number	US-201414914392-A
Country	US
Kind code	A1
Filing date	Jul 16, 2014
Priority date	Aug 29, 2013
Publication date	Jul 21, 2016
Grant date	—

Abstract

A method of manufacturing a hot press formed part by hot pressing a coated steel sheet that is obtained by forming a Zn-based coating layer on a surface of a steel sheet includes: heating the coated steel sheet to a temperature range of 750° C. or more and 1000° C. or less; cooling a surface of the coated steel sheet; and hot press forming the coated steel sheet under a condition that a surface temperature of the coated steel sheet is 400° C. or less and an average temperature of the coated steel sheet is 500° C. or more or a temperature of a center position of the coated steel sheet in a thickness direction is 530° C. or more.

First claim

1 . A method of manufacturing a hot press formed part by hot pressing a coated steel sheet that is obtained by forming a Zn-based coating layer on a surface of a steel sheet, the method comprising:
heating the coated steel sheet to a temperature range of 750° C. or more and 1000° C. or less;
cooling a surface of the coated steel sheet; and
hot press forming the coated steel sheet under a condition that a surface temperature of the coated steel sheet is 400° C. or less and an average temperature of the coated steel sheet is 500° C. or more.

2 . A method of manufacturing a hot press formed part by hot pressing a coated steel sheet that is obtained by forming a Zn-based coating layer on a surface of a steel sheet, the method comprising:
heating the coated steel sheet to a temperature range of 750° C. or more and 1000° C. or less;
cooling a surface of the coated steel sheet; and
hot press forming the coated steel sheet under a condition that a surface temperature of the coated steel sheet is 400° C. or less and a temperature of a center position of the coated steel sheet in a thickness direction is 530° C. or more.

3 . The method of manufacturing a hot press formed part according to claim 1 ,
wherein the coating layer is a Zn—Ni coating layer, and a Ni content in the Zn—Ni coating layer is 9% or more and 25% or less by mass.

4 . The method of manufacturing a hot press formed part according to claim 1 ,
wherein the coating layer is a Zn—Fe coating layer, and a Fe content in the Zn—Fe coating layer is 5% or more and 80% or less by mass.

5 . The method of manufacturing a hot press formed part according to claim 1 ,
wherein the steel sheet has a chemical composition that includes, in % by mass: 0.15% or more and 0.50% or less C; 0.05% or more and 2.00% or less Si; 0.50% or more and 3.00% or less Mn; 0.10% or less P; 0.050% or less S; 0.0002% or more and 0.0050% or less B; 0.10% or less Al; and 0.010% or less N, with a balance including Fe and incidental impurities.

6 . The method of manufacturing a hot press formed part according to claim 5 ,
wherein the chemical composition further includes, in % by mass, at least one type selected from the group consisting of: 0.01% or more and 0.5% or less Cr; 0.01% or more and 0.5% or less V; 0.01% or more and 0.5% or less Mo; and 0.01% or more and 0.5% or less Ni.

7 . The method of manufacturing a hot press formed part according to claim 6 ,
wherein the chemical composition further includes, in % by mass, 0.01% or more and 0.20% or less Ti.

8 . The method of manufacturing a hot press formed part according to claim 7 ,
wherein the chemical composition further includes, in % by mass, 0.01% or more and 0.10% or less Nb.

9 . The method of manufacturing a hot press formed part according to claim 8 ,
wherein the chemical composition further includes, in % by mass, 0.003% or more and 0.03% or less Sb.

10 . (canceled)

11 . The method of manufacturing a hot press formed part according to claim 3 , wherein the steel sheet has a chemical composition that includes, in % by mass: 0.15% or more and 0.50% or less C; 0.05% or more and 2.00% or less Si; 0.50% or more and 3.00% or less Mn; 0.10% or less P; 0.050% or less S; 0.0002% or more and 0.0050% or less B; 0.10% or less Al; and 0.010% or less N, with a balance including Fe and incidental impurities.

12 . The method of manufacturing a hot press formed part according to claim 11 ,
wherein the chemical composition further includes, in % by mass, at least one type selected from the group consisting of: 0.01% or more and 0.5% or less Cr; 0.01% or more and 0.5% or less V; 0.01% or more and 0.5% or less Mo; and 0.01% or more and 0.5% or less Ni.

13 . The method of manufacturing a hot press formed part according to claim 12 ,
wherein the chemical composition further includes, in % by mass, 0.01% or more and 0.20% or less Ti.

14 . The method of manufacturing a hot press formed part according to claim 13 ,
wherein the chemical composition further includes, in % by mass, 0.01% or more and 0.10% or less Nb.

15 . The method of manufacturing a hot press formed part according to claim 14 , wherein the chemical composition further includes, in % by mass, 0.003% or more and 0.03% or less Sb.

16 . The method of manufacturing a hot press formed part according to claim 2 ,
wherein the coating layer is a Zn—Ni coating layer, and a Ni content in the Zn—Ni coating layer is 9% or more and 25% or less by mass.

17 . The method of manufacturing a hot press formed part according to claim 16 ,
wherein the steel sheet has a chemical composition that includes, in % by mass: 0.15% or more and 0.50% or less C; 0.05% or more and 2.00% or less Si; 0.50% or more and 3.00% or less Mn; 0.10% or less P; 0.050% or less S; 0.0002% or more and 0.0050% or less B; 0.10% or less Al; and 0.010% or less N, with a balance including Fe and incidental impurities.

18 . The method of manufacturing a hot press formed part according to claim 17 ,
wherein the chemical composition further includes, in % by mass, at least one type selected from the group consisting of: 0.01% or more and 0.5% or less Cr; 0.01% or more and 0.5% or less V; 0.01% or more and 0.5% or less Mo; and 0.01% or more and 0.5% or less Ni.

19 . The method of manufacturing a hot press formed part according to claim 18 ,
wherein the chemical composition further includes, in % by mass, 0.01% or more and 0.20% or less Ti.

20 . The method of manufacturing a hot press formed part according to claim 19 ,
wherein the chemical composition further includes, in % by mass, 0.01% or more and 0.10% or less Nb.

21 . The method of manufacturing a hot press formed part according to claim 20 , wherein the chemical composition further includes, in % by mass, 0.003% or more and 0.03% or less Sb.

Assignees

• Jfe Steel Corp

Inventors

• Nakagaito Tatsuya
• Tokita Yuichi
• Minote Toru
• Tamai Yoshikiyo

Classifications

• C21D8/02

  during manufacturing of plates or strips (C21D8/12 takes precedence) · CPC title

• C22C38/32

  with boron · CPC title

• C22C38/60

  containing lead, selenium, tellurium, or antimony, or more than 0.04% by weight of sulfur · CPC title

• C21D6/008

  containing Si · CPC title

• C21D8/0221

  characterised by the working steps · CPC title