| 摘要 |
PROBLEM TO BE SOLVED: To obtain the silicon steel having a low iron loss by containing a specified ratio of C, P, N, Si, Mn, Al, further a specified ratio of S, Sb, Sn and the balance Fe with inevitable impurities. SOLUTION: A composition of the steel plate consists of, by weight, <=0.005% C, <=0.2% P, <=0.005% N, <=4% Si, 0.05-1.0% Mn, <=1.5% Al, <=0.001% S, 0.001-0.05% Sb+Sn/2. In the case of near 0.001% S, that is, near 10 ppm, an iron loss reduction is significant but moderate for <=10 ppm. This is due to the fact that a nitride layer generated to a surface layer region prevents grain growth to suppress an iron loss reduction. To this end, nitriding suppression is conducted by adding Sb, Sn. Sn requires an adding quantity of twofolds of Sb for having the same effect as Sb, therefore, Sb and Sn are considered in total and their contents are set to the range shown above. |
