| 摘要 |
PROBLEM TO BE SOLVED: To provide a means for attaining stable growth of secondary recrystallized grains by making the means sufficiently exhibit an inhibitor effect while lowering the heating temperature of a slab for grain-oriented silicon steel sheet and also preventing an abnormal crystalline grain growth at the time of slab heating and controlling the size of the crystalline grains to a proper value. SOLUTION: A slab for grain-oriented silicon steel sheet, having a composition containing, a inhibitor elements, 0.005-0.050% Al, 0.003-0.010% N, <=0.02%, in total, of S and/or Se, and one or <=2 kinds among 0.003-0.3% each of Sb, Sn, Ge, and Bi, is used. In a series of stages for obtaining a grain oriented silicon steel sheet by treating this slab, slab heating is performed at a temp. of <=1300 deg.C under the condition that the inhibitor elements are materially allowed to enter into solid solution and the crystalline grain size of the slab after heating becomes 20 to 30 mm. |
