| 摘要 |
PURPOSE:To improve magnetic properties and bendability by carrying out degreasing after the final cold rolling and also Cu adhesion after decarburizing and primary recrystallization annealing under respectively specified conditions at the time of producing a grain-oriented silicon steel sheet containing S, etc., as inhibitors. CONSTITUTION:A slab for a silicon steel containing one or more elements among S, Se, and Al as inhibitors is hot-rolled and is cold-rolled once or cold-rolled twice while process- annealed between the cold rolling stages so as to be formed to the final sheet thickness. Subsequently, after decarburizing and primary recrystallization annealing is exerted, a separation agent at annealing composed essentially of MgO is applied to the surface of the steel sheet and secondary recrystallization annealing and purification annealing are performed, by which a grain-oriented silicon steel sheet is produced. In the above manufacturing process, the steel sheet is subjected, after the final cold rolling, to degreasing in a silicate based electrolytic degreasing bath in which iron content in the solution is regulated to 50-5000mg/l. Further, after successive decarburizing and primary recrystallization annealing, Cu is allowed to uniformly adhere to the steel sheet surface by 400-2000mg/m<2> per side by means of electroplating or displacement plating. By this method, the grain-oriented silicon steel sheet excellent in bendability as well as in magnetic properties can advantageously be obtained. |
