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. 06, 2022
Filed:
Sep. 15, 2017
Arcelormittal, Luxembourg, LU;
ARCELORMITTAL, Luxembourg, LU;
Abstract
A cold-rolled and heat-treated steel sheet, having a composition including, by weight percent: 0.10%≤C≤0.40%, 3.5%≤Mn≤8.0%, 0.5%≤Si≤2.5%, 0.003%≤Al≤3.0%, with Si+Al≥0.8%, 0.001%≤Mo≤0.5%, S≤0.010%, P≤0.020%, N≤0.008%, and optionally one or more elements selected from a group comprising Cr, Ti, Nb, V and B, such that: 0.01%≤Cr≤2.0%, 0.010%≤Ti≤0.080%, 0.010%≤Nb≤0.080%, 0.010%≤V≤0.30%, 0.0005%≤B≤0.003%, the remainder of the composition being iron and unavoidable impurities resulting from the smelting. The microstructure includes, in surface fraction, between 10% and 50% of retained austenite, at most 8% of fresh martensite, and tempered martensite. The retained austenite includes Mn-enriched austenite, having a Mn content higher than 1.3*Mn %, Mn % designating the Mn content of the steel sheet, a surface fraction of the Mn-enriched austenite with respect to the whole microstructure is between 2% and 12%, and Mn-poor austenite, having an Mn content between 0.5*Mn % and 1.3*Mn %.