| 摘要 |
PROBLEM TO BE SOLVED: To produce a high magnetic flux density grain-oriented silicon steel sheet small in the dispersion of magnetic properties in the width direction by differentiating the temp. in annealing before final intensive cold rolling for a steel having a specified compsn. composed of C, Si, Mn, Al, N, S, Se and Fe between the center part and edge parts. SOLUTION: A continuously cast slab contg., by weight, 0.015 to 0.100% C, 2.0 to 4.0% Si, 0.03 to 0.12% Mn, 0.010 to 0.065% Sol.Al, 0.0040 to 0.0100% N and 0.005 to 0.050% S or Se, furthermore contg., at need, Sb, Sn, Cu, Mo, Ge, B, Te, As and Bi by 0.003 to 0.3%, and the balance substnatially Fe is heated, is thereafter subjected to hot rolling and is subjected to final intensive cold rolling to regulate its sheet thickness into a final one, which is subjected to decarburizing-primary recrystallization annealing and final finish annealing. At this time, in annealing before the final intensive cold rolling, the center part in the width direction is annealed at 800 to 1200 deg.C, the edge parts are annealed at >=780 deg.C and also at a temp. lower than that of the center part, and after that, the center part and edge parts are rapidly cooled. |
