METHOD FOR CONTROLLING PRIMARY RECRYSTALLIZED GRAIN SIZE OF GRAIN ORIENTED SILICON STEEL SHEET

摘要

PROBLEM TO BE SOLVED: To stably prevent the occurrence of inferior secondary recrystallization causing deterioration in the electromagnetic properties of a product by regulating the desired grain size of primary recrystallized grain size control to the optimum grain size determined according to the fluctuation of Al content, at the time of producing a grain oriented silicon steel sheet by using a silicon steel slab of specific composition. ;SOLUTION: The grain oriented silicon steel sheet is produced by using, as a stock, a slab of a silicon steel containing, by weight, 1.5-4.5% Si, 0.005-0.06% Al, and 0.001-0.015% N. In this manufacturing process, at the time of controlling primary recrystallized grain size, the desired grain size of primary recrystallized grain size control is regulated to the optimum grain size determined according to the fluctuation of Al content. For example, the optimum grain size (d) is determined by the relation in equation 1/d=a[log(%Al)]+b in which Al content is represented by (%Al), where (a) and (b) are contants, respectively.;COPYRIGHT: (C)1997,JPO