公开(公告)号：US11473180B2

公开(公告)日：2022-10-18

申请号：US16072668

申请日：2017-01-26

Applicant: JFE Steel Corporation

Inventor： Hiromi Yoshitomi ,  Hiroyuki Masuoka ,  Seisuke Tsuda ,  Yasuhiro Nishimura ,  Masaki Koba

IPC: C23C2/06 ,  C23C2/02 ,  C23C2/28 ,  C23C2/40 ,  C21D9/46 ,  C22C38/14 ,  C22C38/60 ,  C22C38/00 ,  C21D8/02 ,  C22C38/02 ,  C22C38/06 ,  C22C38/08 ,  C22C38/12 ,  C22C38/16 ,  C22C38/22 ,  C22C38/26 ,  C22C38/28 ,  C22C38/32 ,  C22C38/38

Abstract: Provided are a high-yield-ratio high-strength galvanized steel sheet and a method for manufacturing thereof. The high-yield-ratio high-strength galvanized steel sheet has a steel sheet having a specified chemical composition and a metallographic structure including, in terms of area ratio, in terms of area ratio, 15% or less of ferrite, 20% or more and 50% or less of martensite, and bainite and tempered martensite in a total amount of 30% or more, and a galvanized layer formed on the steel sheet having a coating weight of 20 g/m2 to 120 g/m2 per side, in which a yield strength ratio is 65% or more, a tensile strength is 950 MPa or more, and Mn oxides are contained in the galvanized layer in an amount of 0.015 g/m2 to 0.050 g/m2.

公开(公告)号：US20190032187A1

公开(公告)日：2019-01-31

申请号：US16072668

申请日：2017-01-26

Applicant: JFE Steel Corporation

Inventor： HIROMI YOSHITOMI ,  Hiroyuki Masuoka ,  Seisuke Tsuda ,  Yasuhiro Nishimura ,  Masaki Koba

IPC: C23C2/06 ,  C22C38/02 ,  C22C38/06 ,  C22C38/00 ,  C22C38/60 ,  C22C38/16 ,  C22C38/14 ,  C22C38/12 ,  C22C38/38 ,  C22C38/22 ,  C22C38/32 ,  C22C38/26 ,  C22C38/28 ,  C22C38/08 ,  C23C2/40 ,  C23C2/28 ,  C23C2/02 ,  C21D8/02

Abstract: Provided are a high-yield-ratio high-strength galvanized steel sheet and a method for manufacturing thereof. The high-yield-ratio high-strength galvanized steel sheet has a steel sheet having a specified chemical composition and a metallographic structure including, in terms of area ratio, in terms of area ratio, 15% or less of ferrite, 20% or more and 50% or less of martensite, and bainite and tempered martensite in a total amount of 30% or more, and a galvanized layer formed on the steel sheet having a coating weight of 20 g/m2 to 120 g/m2 per side, in which a yield strength ratio is 65% or more, a tensile strength is 950 MPa or more, and Mn oxides are contained in the galvanized layer in an amount of 0.015 g/m2 to 0.050 g/m2.