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. 12, 2011
Filed:
May. 22, 2007
Yoshiyuki Ushigami, Tokyo, JP;
Norikazu Fujii, Tokyo, JP;
Takeshi Kimura, Tokyo, JP;
Maremizu Ishibashi, Tokyo, JP;
Shuichi Nakamura, Tokyo, JP;
Koji Yamasaki, Tokyo, JP;
Yoshiyuki Ushigami, Tokyo, JP;
Norikazu Fujii, Tokyo, JP;
Takeshi Kimura, Tokyo, JP;
Maremizu Ishibashi, Tokyo, JP;
Shuichi Nakamura, Tokyo, JP;
Koji Yamasaki, Tokyo, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
The present invention provides a method of production of grain-oriented electrical steel sheet comprising making a slab heating temperature 1280° C. or less, annealing hot rolled sheet by (a) a process of heating it to a predetermined temperature of 1000 to 1150° C. to cause recrystallization, then annealing by a temperature lower than that of 850 to 1100° C. or by (b) decarburizing in annealing the hot rolled sheet so that a difference in amounts of carbon of the steel sheet before and after annealing the hot rolled sheet becomes 0.002 to 0.02 mass % and performing the heating in the temperature elevation process of the decarburization annealing under conditions of a heating rate of 40° C. or more, preferably 75 to 125° C./s while the temperature of the steel sheet is in a range from 550° C. to 720° C. and utilizing induction heating for rapid heating in the temperature elevation process of decarburization annealing.