| 摘要 |
PROBLEM TO BE SOLVED: To reduce the torque loss of motor by subjecting a stock having a specific composition containing C, Si, Al, S, Mn, P, and N to finish annealing, to temper rolling at a specific draft, and then to magnetic annealing at a specific temperature. SOLUTION: Finish annealing is applied to a stock having a composition containing, by weight, <=0.005% C, <=4% Si, 0.5-3.5% Al, <=0.02% S, 0.05-1.5% Mn, <=0.2% P, and <=0.005% N. Then, the stock is temper rolled at 0.5-10% draft and subjected to magnetic annealing at 850-1000 deg.C. When the content of Al, among the components in the stock, is >=0.5%, α to γ transformation temperature is increased and grain coarsening is brought about by high temperature annealing and hysteresis loss becomes increased; however, the hysteresis- loss-reducing effect becomes saturated when Al content exceeds 3.5%. As the above stock, a stock, prepared by subjecting a molten steel blown in a converter to degassing treatment by a conventional method, to component regulation, to forging, and then to hot rolling and cold rolling to a prescribed sheet thickness, is used. |
