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:
Jan. 28, 2020
Filed:
Nov. 16, 2011
Elijah Kakiuchi, Kobe, JP;
Toshio Murakami, Kobe, JP;
Hideo Hata, Kobe, JP;
Tatsuya Asai, Kakogawa, JP;
Naoki Mizuta, Kakogawa, JP;
Elijah Kakiuchi, Kobe, JP;
Toshio Murakami, Kobe, JP;
Hideo Hata, Kobe, JP;
Tatsuya Asai, Kakogawa, JP;
Naoki Mizuta, Kakogawa, JP;
Kobe Steel, Ltd., Kobe-shi, JP;
Abstract
A high-strength steel sheet has a chemical composition including 0.05% to 0.3% of C, 1% to 3% of Si, 0.5% to 3% of Mn, 0% to 0.1% of P, 0.001% to 0.1% of Al, and 0.002% to 0.03% of N, in mass percent; further includes iron and impurities; and has a structure including 50% to 90% of bainitic ferrite, 5% to 20% of retained austenite (γ), a total of 10% to 50% of martensite and the retained austenite, and 0% to 40% of polygonal ferrite, in area percent based on the entire structure. The retained austenite has a carbon content (Cγ) of 0.5% to 1.2% by mass, an average equivalent circle diameter of 0.2 to 2 μm, and an average aspect ratio (maximum diameter/minimum diameter) of less than 3.0. The high-strength steel sheet excels both in elongation and deep drawability while having a strength of 980 MPa or more.