| 摘要 |
PURPOSE:To manufacture the titled electrical steel sheet at a relatively low cost, by hot-rolling a dead soft steel contg. a small amount of Sn and having a specified weight ratio of B/N and by self-annealing the hot rolled steel plate in the form of a coil or by annealing the plate at a high temp. CONSTITUTION:A steel contg. <=0.015% C, 0.3-2.0% Si, 0.005-0.10% acid-sol. Al, 0.02-0.20% Sn, <=0.007% N and <=0.005% B in 0.5-1.5wt ratio of B/N is hot rolled. The hot rolled steel plate is coiled at >=700 deg.C and self-annealed, or it is annealed at >=850 deg.C. The annealed plate is cold rolled once, or it is cold rolled >=2 times while interposing a process annealing stage, and continuous annealing is finally carried out at >=about 750 deg.C. By this method a nondirectional electrical steel sheet with <=about 4.5w/kg iron loss at W15/50 and >=about 1.71 tesla magnetic flux density at B50 can be obtd. |
