Invention Grant
- Patent Title: High-strength steel sheet and method for producing the same
-
Application No.: US16485197Application Date: 2018-02-09
-
Publication No.: US11408058B2Publication Date: 2022-08-09
- Inventor: Hidekazu Minami , Takashi Kobayashi , Shinjiro Kaneko , Yuji Tanaka
- Applicant: JFE STEEL CORPORATION
- Applicant Address: JP Tokyo
- Assignee: JFE STEEL CORPORATION
- Current Assignee: JFE STEEL CORPORATION
- Current Assignee Address: JP Tokyo
- Agency: Oliff PLC
- Priority: JPJP2017-025490 20170215
- International Application: PCT/JP2018/004515 WO 20180209
- International Announcement: WO2018/151023 WO 20180823
- Main IPC: C22C38/04
- IPC: C22C38/04 ; C22C38/00 ; C22C38/02 ; C22C38/06 ; C22C38/12 ; C22C38/14 ; C22C38/60 ; C23C2/06 ; C21D8/02 ; C21D8/04 ; C21D9/46

Abstract:
There is provided a high-strength steel sheet and a method for producing the same. The steel sheet has a specified chemical composition and a microstructure including, in terms of area percentage, 20.0% or more and 60.0% or less ferrite, 40.0% or more and 80.0% or less of a hard phase composed of bainitic ferrite, tempered martensite, fresh martensite, and retained austenite, 35.0% or more and 55.0% or less bainitic ferrite with respect to the entire hard phase, 20.0% or more and 40.0% or less tempered martensite with respect to the entire hard phase, 3.0% or more and 15.0% or less fresh martensite with respect to the entire hard phase, and 5.0% or more and 20.0% or less retained austenite with respect to the entire hard phase.
Information query