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:
Jun. 16, 2026
Filed:
Dec. 20, 2018
Posco, Pohang-si, KR;
Min-Seo Koo, Gwangyang-si, KR;
In-Shik Suh, Pohang-si, KR;
POSCO CO., LTD, Gyeongsangbuk-Do, KR;
Abstract
An ultrahigh strength cold-rolled steel sheet and a manufacturing method thereof are provided. An ultrahigh strength cold-rolled steel sheet, according to a preferred aspect of the present invention, comprises, in percentage by weight: C: 0.25 to 0.4%; Si: 0.5% or less (excluding 0); Mn: 3.0 to 4.0%; P: 0.03% or less (excluding 0); S: 0.015% or less (excluding 0); Al: 0.1% or less; Cr: 1% or less (excluding 0); Ti: 48/14*[N] to 0.1% or less; Nb: 0.1% or less (excluding 0); B: 0.005% or less (excluding 0); N: 0.01% or less (excluding 0); and a balance of Fe and unavoidable impurities, and a microstructure includes 90% or more (including 100%) of martensite, and one or two kinds of 10% or less (including 0%) of ferrite and bainite.