| 摘要 |
A high-strength electrical steel sheet is produced by a series of steps involving heating a slab which comprises a predetermined component composition, subjecting the slab to hot rolling which comprises rough rolling and finish rolling, then subjecting the slab to hot band annealing, pickling the slab, then cold-rolling the slab once to the final sheet thickness thereof, and final-annealing the slab, wherein: the cumulative rolling reduction ratio in said rough rolling is 73.0% or greater; in said hot band annealing step, annealing conditions are selected such that, under conditions where the annealing temperature is between 850°C and 1000°C inclusive and the annealing time is between 10 seconds and 10 minutes inclusive, the area percentage of recrystallized grains in a cross section along the steel sheet rolling direction after said hot band annealing becomes 100% and the recrystallized grain size falls between 80 µm and 300 µm inclusive; and in said final annealing step, annealing conditions are selected such that, under conditions where the annealing temperature is between 670°C and 800°C inclusive and the annealing time is between 2 seconds and 1 minute inclusive, the area percentage of recrystallized grains in a cross section along the steel sheet rolling direction after said final annealing falls between 30% and 95% inclusive and the length, in the rolling direction, of a group of connected non-recrystallized grains becomes 2.5 mm or shorter. |
