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:
Aug. 01, 2023
Filed:
Apr. 23, 2019
Nippon Steel Corporation, Tokyo, JP;
Shinichiro Tabata, Tokyo, JP;
Yoshihiro Suwa, Tokyo, JP;
Kazuo Hikida, Tokyo, JP;
Kazuhisa Kusumi, Tokyo, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
A steel member according to an aspect of the present invention has a predetermined chemical composition, in which a metallographic structure includes, by a volume %, 60.0% to 85.0% of martensite, 10.0% to 30.0% of bainite, 5.0% to 15.0% of residual austenite, and 0% to 4.0% of a remainder in microstructure. A length of a maximum minor axis of the residual austenite is 30 nm or longer. A number density of a carbide which exist in the steel member and has a circle equivalent diameter of 0.1 μm or more and an aspect ratio of 2.5 or less is 4.0×10pieces/mmor less.