| 摘要 |
PURPOSE:To produce a nonoriented silicon steel sheet at a low cost by means of direct rolling without causing deterioration in magnetic properties and productivity by properly regulating respective contents of Mn, S, and Al in a steel stock and the value of Mn/S at the time of producing a low grade nonoriented silicon steel sheet. CONSTITUTION:A continuously cast slab of low Si content which has a composition consisting of, by weight, <=0.0050% C, 0.1-1.0% Si, 0.5-1.5% Mn, <=0.15% P, 0.003-0.015% S, 0.01-0.40% Al, <=0.0050% N, and the balance Fe and satisfying an inequality I is cooled down to 1000-1100 deg.C at a cooling rate CR( deg.C/min) satisfying an inequality II, subjected, without holding nor reheating, to hot rolling without delay at >=650 deg.C coiling temp., pickled to undergo descaling, cold-rolled, annealed at 700-900 deg.C, and subjected, if necessary, to application of insulating film and to baking, by which the nonoriented silicon steel sheet can be produced at a low cost. |
