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:
Mar. 15, 2016
Filed:
May. 23, 2011
Noriaki Kohsaka, Kanagawa, JP;
Kazuhiro Seto, Chiba, JP;
Hidetaka Kawabe, Chiba, JP;
Yasushi Tanaka, Tokyo, JP;
Noriaki Kohsaka, Kanagawa, JP;
Kazuhiro Seto, Chiba, JP;
Hidetaka Kawabe, Chiba, JP;
Yasushi Tanaka, Tokyo, JP;
JFE Steel Corporation, , JP;
Abstract
A high strength hot-rolled steel sheet with a tensile strength of not less than 590 MPa which exhibits excellent bake hardenability and stretch-flangeability has a chemical composition including, in terms of mass %, C at 0.040 to 0.10%, Si at not more than 0.3%, Mn at 1.7 to 2.5%, P at not more than 0.030%, S at not more than 0.005%, Al at not more than 0.1% and N at 0.006 to 0.025%, and microstructure wherein a bainite phase represents not less than 60%, the total of a ferrite phase and a pearlite phase represents not more than 10%, and the bainite phase includes grains among which cementite grains have been precipitated at not less than 1.4×10grains/mmand the cementite grains have an average grain diameter of not more than 1.5 μm.