Patent ID: 11459633

Abstract:
In a production of a grain-oriented electrical steel sheet by subjecting a steel slab containing a particular composition and further including an inhibitor-forming ingredient to hot rolling, hot-band annealing, cold rolling, primary recrystallization annealing combined with decarburization annealing and finish annealing, the steel slab satisfies a given relation between a content ratio of sol. Al to N and a final sheet thickness, and, in the finish annealing, the steel sheet is kept at a temperature zone of higher than 850° C. but not higher than 950° C. in heating process for 5 to 200 hours, heated to a temperature zone of 950 to 1050° C. at 5 to 30° C./hr and further subjected to purification treatment of keeping a temperature of not lower than 1100° C. for not less than 2 hours to provide a secondary recrystallization structure that has an average value of a diameter equivalent to a circle of 10 to 100 mm.