| 摘要 |
PURPOSE:To improve the electromagnetic characteristic of a silicon steel sheet in the stage of producing a grain oriented silicon steel sheet by hot rolling and cold rolling of a silicon steel slab by holding the central temp. of the slab in a specific temp. range in an induction heating furnace prior to hot rolling and maintaining the specific relation between said temp. and the surface temp. of the slab. CONSTITUTION:The silicon steel slab contg., by weight %, 0.025-0.080% C, 2.0-4.5% Si, 0.02-0.10% Mn and 0.005-0.10% in total of at least one kind selected from S, Se, Al and B as an inhibitor component is heated up in the induction heating furnace in which a non-oxidizing atmosphere is maintained prior to hot rolling to maintain the relation 50 deg.C>=Ts-Tc>=-100 deg.C between the central temp. Tc of the slab and the surface temp. Ts in a 1,300-1,380 deg.C by the heat conduction from the surface layer toward the central part of the slab. The slab is held in this state for >=10min. The slab is subjected to ordinary hot rolling and cold rolling in succession of above to 0.15-0.5mm final sheet thickness. The grain oriented silicon steel sheet having the excellent magnetic characteristic in the rolling direction is thus produced. |
