| 摘要 |
PROBLEM TO BE SOLVED: To produce a silicon steel sheet excellent in workability such as punchability, machinability or the like. SOLUTION: This steel sheet has a chemical compsn. composed of, by weight, <=0.01% C, 0.01 to 4.50% Si, 0.0001 to 4.00% sol.Al, 0.05 to 4.00% Mn, <=0.15% P, 0.005 to 0.035% S, and the balance Fe with inevitable impurities, in which inclusions in the steel sheet are composed of oxide inclusions, sulfide inclusions, and composite inclusions of both, the size of each inclusion is >=2 μm, 2 to 10 pieces of the inclusions form a group so as to be connected in a row, and the total of the number of the inclusions of >=2 μm grain size is controlled to >=10% to the number of the inclusions of >=0.1 μm grain size. As for the producing method, molten steel is subjected to vacuum treatment to control the contents of C, P and S to the ranges in the above chemical compsn., the content of dissolved oxygen is controlled to 0.01 to 0.07 wt.%, next, the contents of sol.Al and Si are controlled to the ranges in the above chemical compsn., then, the content of Mn is controlled to the range in the above chemical compsn., and, after that, casting, hot rolling, cold rolling and annealing are executed according to the conventional methods. |
