| 摘要 |
PURPOSE: To obtain a nonoriented silicon steel sheet having the magnetic properties of low core loss and high magnetic flux density at a low cost without executing twice of cold rolling before and after high temp. heating and process annealing of slab. CONSTITUTION: At the time of melting a steel having a compsn. contg. <=0.004% C, <=1.0% Si, <=0.4% Mn, <=0.004% N, <=0.006% S and <=0.015% O, satisfying Mn/S>=10, and the balance Fe with inevitable impurities, the melting is executed in such a manner that the content of sol.Al before the addition of the alloy elements is regulated to <=0.001% to form into a slab, which is heated to 1000 to 1300 deg.C, is thereafter subjected to hot rolling, is coiled at >=650 deg.C and is subjected to cold rolling at >=75% draft. Thus, the nonoriented silicon steel sheet excellent in the magnetic properties of low core loss and high magnetic flux density as the material for an iron core for rotating apparatus can be produced. |
