| 摘要 |
PROBLEM TO BE SOLVED: To produce a nonoriented silicon steel sheet excellent in magnetic properties, in producing a nonoriented silicon steel sheet from molten steel having a specified componental compsn., by regulating the mixing ratio of a Ca alloy used for desulfurization till the completion of continuous casting to desulfurizing flux to a proper range. SOLUTION: Molten steel contg., by weight, <=0.01% C, <=3.5% Si, <=1.5% Mn, <=2.5% Al, <=0.01% S and <=0.1% P is subjected to continuous casting into a slab, which is successively subjected to hot rolling, cold rolling and finish annealing to produce a nonoriented silicon steel sheet. At this time, till the completion of the continuous casting, desulfurization is executed in such a manner that a Ca alloy and desulfurizing flux are mixed, the amt. of the Ca alloy to be added at the time of the desulfurization is regulated to 0.2 to <1.0kg/t, and the ratio of the amounts to be added between the Ca alloy and the desulfurizing flux is regulated to the range of 0.50<=CaSi/desulfurizing flux <=5.0 by weight ratio. In this way, the nonoriented silicon steel sheet excellent in iron core characteristics under good grain growability can inexpensively be obtd. |
