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. 03, 1990
Filed:
Jan. 25, 1989
Nippon Steel Corporation, Tokyo, JP;
Abstract
Disclosed is a process for the preparation of a grain oriented silicon steel about sheet having a high flux density, which comprises hot-rolling a slab comprising 1.5 to 4.8% by weight of Si, 0.012 to 0.050% by weight of Al, 0.0010 to 0.0120% by weight of N, 0.0020 to 0.0150% by weight of Ti, up to 0.45% by weight of Mn and up to 0.012% by weight of at least one member selected S and Se, which satisfies the requirement 0.06 to 0.6 of Ti/N (at % ratio) and Mn/(S+Se).gtoreq.4.0 (weight ratio) with the balance comprising Fe and unavoidable impurities, to cold-rolling, performing decarburization annealing, coating an annealing separator on the steel sheet surface, then performing finish annealing, and performing a nitriding treatment of the steel sheet during the period of from the point of termination of final cold rolling to the point of initiation of secondary recrystallization at the finish annealing step.