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:
Oct. 23, 2018
Filed:
Mar. 28, 2014
Jfe Steel Corporation, Tokyo, JP;
Shusaku Takagi, Tokyo, JP;
Akihide Nagao, Tokyo, JP;
JFE Steel Corporation, Tokyo, JP;
Abstract
A steel material includes: a composition containing, by mass, C: 0.05% to 0.60%, Si: 0.01% to 2.0%, Mn: 0.3% to 3.0%, P: 0.001% to 0.040%, S: 0.0001% to 0.010%, N: 0.0001% to 0.0060%, Al: 0.01% to 1.5%, one or more elements selected from Ti: 0.01% to 0.20%, Nb: 0.01% to 0.20%, and V: 0.01% or more and less than 0.05%, and one or more elements selected from B: 0.0001% to 0.01%, Mo: 0.005% to 2.0%, and Cr: 0.005% to 3.0%, with the balance being Fe and inevitable impurities; and a steel microstructure that includes 95% or more of tempered martensite on a volume fraction basis, that includes a precipitate having a diameter of 100 nm or less and including one or more elements selected from Ti, Nb, and V and one or more elements selected from carbon and nitrogen at a density of 50 particles/μmor more, and that includes prior austenite having a grain diameter of 3 μm or more.