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. 25, 1990
Filed:
Apr. 19, 1989
Hisashi Kobayashi, Kitakyushu, JP;
Katsuro Kuroki, Kitakyushu, JP;
Masayoshi Minakuchi, Kitakyushu, JP;
Kenichi Yakashiro, Kitakyushu, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
The present invention relates to an improvement in the technique of heating an electrical steel slab at a low temperature. A grain-oriented electrical steel sheet having excellent magnetic characteristics and film characteristics is prepared by the process characterized in that a slab comprising, as main ingredients, up to 0.012% by weight of S, 0.010 to 0.060% by weight of acid-soluble Al, up to 0.010% by weight of N, 0.08 to 0.45% by weight of Mn, and 0.015 to 0.045% by weight is used as the starting slab, and after the decarburization annealing, the nitriding treatment is carried out at a temperature of 500.degree. to 900.degree. C. in an atmosphere having an NH.sub.3 gas concentration of at least 1000 ppm, while running the strip.