| 摘要 |
PURPOSE:To produce a grain-oriented silicon steel sheet capable of forming a stable Goss structure by final annealing in a short time and high in magnetic flux density. CONSTITUTION:Steel having a compsn. contg., by weight, <=0.01% C, 2.5 to 7% Si, <=0.01% S, <=0.01% Al, <=0.01% N, <=0.01% Cu, <=5ppm Nb, <=10ppm Sn and <=20ppm Ti and satisfying [Nb]+0.5X-[Sn]+0.25[Ti]<=8, and the balance Fe with inevitable impurities is held to >=1000 deg.C, thereafter subjected to hot rolling so as to regulate the finishing temp. into 700 to 950 deg.C, then subjected to primary cold rolling at 30 to 85% rolling ratio, subsequently annealed at 600 to 900 deg.C, and moreover subjected to secondary cold rolling at 40 to 80% rolling ratio. After that, it is annealed at 600 to 900 deg.C, is furthermore subjected to third cold rolling at 50 to 75% rolling ratio and is annealed at 1000 to 1300 deg.C for <=10min in a reducing atmosphere of hydrogen or the like to obtain the grain-oriented silicon steel sheet high in magnetic flux density. |
