| 摘要 |
PURPOSE:To develop a low-iron loss grain-oriented electromagnetic steel sheet which decreases the deterioration of the magnetic characteristic owing to stress relief annealing by removing part of the base iron of the grain-oriented electromagnetic steel sheet subjected to finish annealing or formed with an insulating film after the finish annealing then subjecting the steel sheet to a phosphoric acid tensed film treat ment. CONSTITUTION:The grain-oriented electromagnetic steel sheet formed by subjecting a silicon steel slab contg.<4% Si to hot rolling, cold rolling and secondary recrystallization annealing or further coating of an insulating film thereon and baking of the coating is marked off to the wire- or spot shape at 5-10mm intervals, 0.1-0.4mm width, 0.02-0.1mm depth and <=0.3mm inter-spot distance or is irradiated with laser light to the insulating film by which the insulating film is stripped and part of the base metal is removed. A metal is plated to the part from which the base iron is removed and thereafter said part is subjected to the phosphoric acid tensed film treatment, by which the low-iron loss grain-oriented electromagnetic steel sheet without having the deterioration of the magnetic characteristic owing to the stress relief annealing is produced. |
