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. 26, 2013
Filed:
Feb. 02, 2007
Suguhiro Fukushima, Osaka, JP;
Manabu Eto, Osaka, JP;
Tamotsu Sasaki, Osaka, JP;
Kaori Kawano, Osaka, JP;
Masayuki Wakita, Osaka, JP;
Suguhiro Fukushima, Osaka, JP;
Manabu Eto, Osaka, JP;
Tamotsu Sasaki, Osaka, JP;
Kaori Kawano, Osaka, JP;
Masayuki Wakita, Osaka, JP;
Nippon Steel & Sumitomo Metal Corporation, Tokyo, JP;
Abstract
A method for manufacturing a hot-rolled sheet is provided, wherein the method attains grain refinement of the steel sheet containing C, Si, and Mn, wherein the grain size thereof is set to particularly below average of 2 μm, which has ferrite grain with equiaxed morphology, which has high formability in forming, and the ferrite grain-size deviation in the thickness direction is uniformed down to the level not higher than a predetermined amount whereby uniform formability in forming is high. The method includes a first rolling for rolling the sheet such that the total rolling reduction is 80% or more or the average grain size is 30 μm or less in a form of single phase of austenite, a second rolling of a single-pass, a third rolling being conducted thereafter, and a following cooling.