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:
Jan. 19, 2021
Filed:
Mar. 31, 2017
Nippon Steel Corporation, Tokyo, JP;
Tatsuo Yokoi, Tokyo, JP;
Nobuo Yoshikawa, Tokyo, JP;
Shigeru Yonemura, Tokyo, JP;
Kazuya Ootsuka, Tokyo, JP;
NIPPON STEEL CORPORATION, Tokyo, JP;
Abstract
A hot rolled steel sheet including a chemical composition consisting of, in mass %, C: 0.07-0.22%, Si: 1.00-3.20%, Mn: 0.80-2.20%, Al: 0.010-1.000%, N≤0.0060%, P≤0.050%, S≤0.005%, Ti: 0-0.150%, Nb: 0-0.100%, V: 0-0.300%, Cu: 0-2.00%, Ni: 0-2.00%, Cr: 0-2.00%, Mo: 0-1.00%, B: 0-0.0100%, Mg: 0-0.0100%, Ca: 0-0.0100%, REM: 0-0.1000%, Zr: 0-1.000%, Co: 0-1.000%, Zn: 0-1.000%, W: 0-1.000%, Sn: 0-0.050%, the balance: Fe and impurities, wherein a metal microstructure includes, in area %, at a position ¼ W or ¾ W from an end face of the steel sheet and ¼ t or ¾ t from a surface, retained austenite: more than 2%-10%, martensite ≤2%, bainite: 10-70%, pearlite ≤2%, the balance: ferrite, an average circle-equivalent diameter of a metallic phase constituted of retained austenite/martensite is 1.0 to 5.0 μm, an average of minimum distances between adjacent metallic phases is 3 μm or more, and a standard deviation of nano hardness is 2.5 GPa or less.