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.

Date of Patent:
Dec. 17, 2024

Filed:

Dec. 19, 2019
Applicant:

Posco, Pohang-si, KR;

Inventors:

Hang-Sik Cho, Gwangyang-si, KR;

Young-Roc Im, Gwangyang-si, KR;

Assignee:

POSCO CO., LTD, Pohang-si, KR;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C21D 9/46 (2006.01); C21D 8/02 (2006.01); C22C 38/00 (2006.01); C22C 38/02 (2006.01); C22C 38/04 (2006.01); C22C 38/06 (2006.01); C22C 38/22 (2006.01); C22C 38/28 (2006.01); C22C 38/32 (2006.01); C23C 2/04 (2006.01); C23C 2/40 (2006.01);
U.S. Cl.
CPC ...
C21D 9/46 (2013.01); C21D 8/0236 (2013.01); C21D 8/0247 (2013.01); C22C 38/001 (2013.01); C22C 38/002 (2013.01); C22C 38/02 (2013.01); C22C 38/04 (2013.01); C22C 38/06 (2013.01); C22C 38/22 (2013.01); C22C 38/28 (2013.01); C22C 38/32 (2013.01); C23C 2/04 (2013.01); C23C 2/40 (2013.01); C21D 2211/001 (2013.01); C21D 2211/002 (2013.01); C21D 2211/005 (2013.01); C21D 2211/008 (2013.01);
Abstract

A high-strength cold-rolled steel sheet having excellent bending workability includes, by weight %, 0.13-0.25% of carbon (C), 1.0-2.0% of silicon (Si), 1.5-3.0% of manganese (Mn), 0.08-1.5% of aluminum (Al)+chromium (Cr)+molybdenum (Mo), 0.1% or less of phosphorus (P), 0.01% or less of sulfur (S), 0.01% or less of nitrogen (N), the remainder of Fe and inevitable impurities, and comprises, by area fraction, 3-25% of ferrite, 20-40% of martensite, and 5-20% of retained austenite, in which a nickel-rich layer formed of nickel (Ni) introduced from the outside is provided on a surface layer portion, and the concentration of nickel (Ni) at a depth of 1 μm from the surface may be greater than or equal to 0.15 wt %.


Find Patent Forward Citations

Loading…