| 摘要 |
PURPOSE:To remove the occurrence of fogging and to obtain a grain-oriented silicon steel sheet excellent in film characteristics by inhibiting reduction in a surface oxide layer in the course between the completion of decarburizing treatment and nitriding treatment and also in the course of subsequent nitriding treatment at the time of producing a grain-oriented silicon steel sheet. CONSTITUTION:At the time of producing a grain-oriented silicon steel sheet by subjecting a silicon steel slab to heating up to <=1200 deg.C and to hot rolling, subjecting the resulting plate, in an as-hot-rolled state or after hot rolled plate annealing, to cold rolling once or to cold rolling twice or more while performing process annealing between cold rolling stages, forming an inhibitor by means of decarburizing and nitriding treatments, and then exerting finish annealing, the degree of oxidation, PH2O/PH2, of an atmospheric gas in a furnace is, i.e., regulated to >=5X10<-4> in the course between the completion of decarburizing annealing and nitriding treatment and also in the course of subsequent nitriding treatment. |
