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. 23, 2007
Yoshiyuki Ushigami, Tokyo, JP;
Norikazu Fujii, Tokyo, JP;
Tomoji Kumano, Tokyo, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
In a production of grain-oriented electrical steel sheet that is heated at a temperature of not higher than 1350° C., (a) the hot-rolled sheet is heated to a prescribed temperature of 1000° C. to 1150° C., and after recrystallization is annealed for a required time at a lower temperature of 850° C. to 1100° C., or (b) in the hot-rolled sheet annealing process decarburization is conducted to adjust the difference in the amount of carbon before and after decarburization to 0.002 to 0.02 mass %. In the temperature elevation process used in the decarburization annealing of the steel sheet, heating is conducted in the temperature range of 550° C. to 720° C. at a heating rate of at least 40° C./s, preferably 75 to 125° C./s, utilizing induction heating for the rapid heating used in the temperature elevation process in decarburization annealing.