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:
Dec. 01, 2015
Filed:
Sep. 15, 2011
Hayato Saito, Fukuyama, JP;
Katsumi Nakajima, Kawasaki, JP;
Yoshimasa Funakawa, Chiba, JP;
Noriaki Moriyasu, Chiba, JP;
Takayuki Murata, Kawasaki, JP;
Hayato Saito, Fukuyama, JP;
Katsumi Nakajima, Kawasaki, JP;
Yoshimasa Funakawa, Chiba, JP;
Noriaki Moriyasu, Chiba, JP;
Takayuki Murata, Kawasaki, JP;
JFE Steel Corporation, Tokyo, JP;
Abstract
A steel sheet including C at 0.05 to 0.15%, Si at 0.2 to 1.2%, Mn at 1.0 to 2.0%, P at not more than 0.04%, S at not more than 0.0030%, Al at 0.005 to 0.10%, N at not more than 0.005% and Ti at 0.03 to 0.13%, the balance being Fe and inevitable impurities, includes surface regions having an area fraction of bainite of less than 80% and an area fraction of a ferrite phase with a grain diameter of 2 to 15 μm of not less than 10%, the surface regions extending from both surfaces of the steel sheet each to a depth of 1.5 to 3.0% relative to a total sheet thickness, as well as an inner region other than the surface regions having an area fraction of a bainite phase of more than 95%, and has a tensile strength of not less than 780 MPa.