| 摘要 |
Provides is a method of producing a grain oriented electrical steel sheet by heating a steel slab having a composition containing by mass% C: 0.0005 % to 0.005 %, Si: 2.0 % to 4.5 %, Mn: 0.005 % to 0.3 %, S and/or Se (in total): 0.05 % or less, sol.Al: 0.010 % to 0.04 %, N: 0.005 % or less, the balance being Fe and incidental impurities, then subjecting the slab to hot rolling to obtain a hot rolled sheet, then optionally subjecting the hot rolled sheet to hot band annealing and subsequent cold rolling once, or twice or more with intermediate annealing performed therebetween to obtain a cold rolled sheet with final sheet thickness, then subjecting the cold rolled sheet to primary recrystallization annealing and subsequent secondary recrystallization annealing, in which the aging index AI of the steel sheet before final cold rolling is set to 70 MPa or less to effectively grow Goss-oriented grains to thereby obtain a grain-oriented electrical steel sheet with good magnetic properties, without the restriction of containing a relatively large amount of C. |
