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. 08, 2025
Filed:
Oct. 27, 2020
Jfe Steel Corporation, Tokyo, JP;
JFE Steel Corporation, Tokyo, JP;
Abstract
In a production of a grain-oriented electrical steel sheet comprising hot rolling a raw steel material, cold rolling, decarburization annealing, applying an annealing separator composed mainly of MgO, finish annealing and magnetic domain subdividing, the annealing separator including certain compounds, and the finish annealing conducted by holding the steel sheet at a temperature of 800 to 950° C. for 10 to 100 hours and passing a dry gas containing not less than 1 vol % of Hand having a dew point of not higher than 10° C. to reach a furnace pressure of not less than 3.5 mmHO from not lower than 1050° C. to a purification treatment temperature, so that a pickling weight loss of undercoat film by pickling with HCl is not more than 1.8 g/mand the total concentration of Sn, Sb, Mo, and W on a boundary face between the film and iron matrix is 0.01 to 0.15 mass %.