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:
Jul. 08, 2025
Filed:
Jun. 24, 2020
Baoshan Iron & Steel Co., Ltd., Shanghai, CN;
BAOSHAN IRON & STEEL CO., LTD., Shanghai, CN;
Abstract
Disclosed is a cold-rolled strip steel with varying strength/hardness in a thickness direction, comprising chemical elements in the following mass percentages: C 0.06-0.3 wt %, Si 0.01-2.5 wt %, Mn 0.5-3 wt %, Al 0.02-0.08 wt % and a balance of Fe and other unavoidable impurities, wherein the cold-rolled strip steel with varying strength/hardness in a thickness direction has a yield strength of ≥420 MPa, a tensile strength of ≥800 MPa, an elongation of ≥11%, and a hardness difference between two surfaces of at least 30 HV, and a method for manufacturing a cold-rolling strip steel with varying strength and hardness thereof in a thickness direction, which is characterized in that, when quenching is performed in the continuous annealing step, an asymmetric quenching and cooling process is performed on both surfaces of the strip steel.