| 摘要 |
PURPOSE:To easily produce the steel sheet excellent in magnetic properties, weldability, and space factor by specifying rolls for rolling used in the former stage of the final pass and in the final pass, respectively, in a cold rolling stage at the time of producing a grain-oriented silicon steel sheet. CONSTITUTION:A grain-oriented silicon steel sheet is produced by a series of stages consisting of cold-rolling a hot rolled plate containing <=0.010wt.% C and <=2.5wt.% Si, annealing the resulting sheet, and forming an insulating film on the above sheet. At this time, as rolls for rolling in the former stage of the final pass in cold rolling, rolls in the surfaces of which craters having shapes where a diameter D expressed in terms of a circle and a difference (h) between the most projecting part and the most recessed part are regulated to <=500mu and 3-40mu, respectively, are arranged so that the number of the craters per square centimeter of unit area is regulated to 1-400 pieces and also the craters are not superimposed are used. Further, bright rolls are used as the rolls for rolling in the final pass and slight-degree rolling is performed at 0.3-5.0% rolling reduction. By this method, ruggedness pattern can be provided in the surface of the steel sheet and the projecting parts can be uniformized, and the grain- oriented silicon steel sheet excellent in magnetic properties, weldability, and space factor can be obtained. |
