| 摘要 |
PURPOSE: To produce a grain oriented silicon steel sheet excellent in magnetic property by subjecting to cold rolling, decarburizing annealing, nitriding annealing and finishing annealing after a high silicon and low carbon steel is heated to relatively low temp. and hot rolled to sheet under the specified condition. CONSTITUTION: After a silicon steel slab containing, by weight, <=0.075% C, 2.5-4.0% Si, that is, Si/C <=60 high silicon/low carbon, 0.05-4.05 Mn, <=0.0155 S, 0.010-0.050% acid soluble Al, 0.0010-0.012% N, further a small quantity of Sn, Cr is heated to a relatively low temp. of <=128 deg.C, it is hot rolled to be made to sheet. At this time, the differential peripheral speed rolling temp. to generate plastic flow unsymetrical in the thickness direction of hot rolled sheet is 1150-950 deg.C, as neccesary after hot rolling, the cold rolling of one or >=2 times including intermediate annealing is executed under the condition of at >80% final rolling rate the final sheet thickness is obtained. Subsequently decarburizing annealing, nitriding annealing and finishing annealing are executed. Thus, the grain oriented silicon steel sheet excellent in magnetic property is produced. |
