The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 25, 2025
Filed:
Mar. 25, 2021
Jfe Steel Corporation, Tokyo, JP;
Lingling Yang, Tokyo, JP;
Yoshiyasu Kawasaki, Tokyo, JP;
Hidekazu Minami, Tokyo, JP;
Tatsuya Nakagaito, Tokyo, JP;
Shotaro Terashima, Tokyo, JP;
Shunsuke Yamamoto, Tokyo, JP;
Katsuya Hoshino, Tokyo, JP;
Yuki Takeda, Tokyo, JP;
JFE STEEL CORPORATION, Tokyo, JP;
Abstract
A steel sheet having a tensile strength (TS) of 780 MPa or more and less than 1180 MPa, high LME resistance, and good weld fatigue properties. The steel sheet has a specific chemical composition and a specific steel microstructure. Crystal grains containing an oxide of Si and/or Mn in a region within 4.9 μm in a thickness direction from a surface of the steel sheet have an average grain size in the range of 3 to 10 μm, the lowest Si concentration Land the lowest Mn concentration Lin the region within 4.9 μm in the thickness direction from the surface of the steel sheet and a Si concentration Tand a Mn concentration Tat a quarter thickness position of the steel sheet satisfy a specified formula.