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:
Sep. 30, 1980
Filed:
Sep. 13, 1979
Nippon Steel Corporation, , JP;
Abstract
A grain oriented electrical silicon steel sheet containing aluminium and having an extremely high magnetic flux density, for example, a B8 of 1.90 or more, is produced by a secondary recrystallization annealing operation in which, during the period of elevating the temperature of a reducing atmosphere to a level within a range of from 850.degree. to 950.degree. C., the partial pressure of nitrogen in the reducing atmosphere is limited to 20% or less based on the entire pressure of the reducing atmosphere, and during the period of elevating the temperature of the reducing atmosphere in which the secondary recrystallization is in progress, the partial pressure of nitrogen is maintained at a level of at least 3%.