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. 24, 2020
Filed:
Mar. 26, 2015
Applicant:
Jfe Steel Corporation, Tokyo, JP;
Inventors:
Assignee:
JFE STEEL CORPORATION, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C21D 9/46 (2006.01); C22C 38/60 (2006.01); C22C 38/32 (2006.01); C22C 38/18 (2006.01); C22C 38/00 (2006.01); C22C 38/08 (2006.01); C22C 38/06 (2006.01); C22C 38/04 (2006.01); C22C 38/02 (2006.01); C21D 8/02 (2006.01); C22C 38/12 (2006.01);
U.S. Cl.
CPC ...
C21D 9/46 (2013.01); C21D 8/0226 (2013.01); C21D 8/0263 (2013.01); C22C 38/00 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/008 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/08 (2013.01); C22C 38/12 (2013.01); C22C 38/18 (2013.01); C22C 38/32 (2013.01); C22C 38/60 (2013.01); C21D 2211/003 (2013.01); C21D 2211/005 (2013.01); C21D 2211/009 (2013.01);
Abstract
A high-carbon hot-rolled steel sheet having a chemical composition containing, by mass %, C: more than 0.40% and 0.63% or less, Si: 0.10% or less, Mn: 0.50% or less, P: 0.03% or less, S: 0.010% or less, sol.Al: 0.10% or less, N: 0.0050% or less, B: 0.0005% or more and 0.0050% or less, and at least one of Sb, Sn, Bi, Ge, Te, and Se in an amount of 0.002% or more and 0.030% or less in total. The steel sheet has a microstructure including ferrite and cementite, in which the density of cementite in ferrite grains is 0.13 pieces/μmor less. Additionally, the steel sheet has a hardness of 81 or less in terms of HRB and a total elongation of 33% or more.