| 摘要 |
PROBLEM TO BE SOLVED: To provide a nonoriented silicon steel sheet having high magnetic flux density and low iron loss. SOLUTION: A slag, having a composition consisting of, by weight, either or both of 0.1-4% Si and 0.1-2% Mn, further either or both of 0.01-0.5% Sn and 0.01-0.5% Sb, and the balance Fe with inevitable impurities, is roughly rolled into sheet bar and then finish-hot-rolled at >=75% total draft and at 800 to 1100 deg.C finishing temperature under the condition that inequality Z=log εexp[32,100/(273+t)]}>=12.1-x [where (ε), (t), and (x) are strain rate (1/s), rolling temperature ( deg.C), and the sum of respective weight concentrations of Sn and Sb, respectively] is satisfied at least at one pass and the sum of draft at the passes satisfying the inequality is regulated to >=20%. The resultant hot rolled plate is coiled at 750 to 1050 deg.C, self-annealed by the retained heat of the coil itself for 5 min to 3 hr, and subjected to a single cold rolling stage. The resultant steel sheet is finish-annealed and then subjected or not subjected to skin pass rolling at 2 to 10% draft. |
