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:
Sep. 30, 2025
Filed:
Dec. 21, 2017
Posco, Pohang-si, KR;
Chang-Hyo Seo, Gwangyang-si, KR;
Yeon-Sang Ahn, Gwangyang-si, KR;
POSCO CO., LTD, Pohang-si, KR;
Abstract
Provided are a cold-rolled steel sheet and a method for manufacturing same, the steel sheet containing, by weight %, 0.03 to 0.07% of C, 0.3% or less of Si, 2.0 to 3.0% of Mn, 0.01 to 0.10% of Sol·Al, 0.3 to 1.2% of Cr, 0.03 to 0.08% of Ti, 0.01 to 0.05 of Nb, 0.0010 to 0.0050% of B, 0.001-0.10% of P, 0.010% or less of S, 0.010% or less of N, the balance being Fe and other impurities, and having a microstructure comprising 75% or more to less than 87% by area of a transformed structure and 13 to 25% by area of ferrite, wherein the transformed structure includes martensite and bainite, the martensite has an average particle diameter of 2 μm or less, the bainite has an average particle diameter of 3 μm or less, the bainite fraction of 3 μm or more is 5% or less.