| 摘要 |
In a method for producing a grain-oriented electrical steel sheet by hot rolling a steel slab containing, in terms of mass%, C: 0.001ˆ¼0.20%, Si: 1.0ˆ¼5.0%, Mn: 0.03ˆ¼1.0%, one or two of S and Se: 0.005ˆ¼0.040% in total, sol. Al: 0.003ˆ¼0.050% and N: 0.0010ˆ¼0.020%, subjecting to a cold rolling to a final thickness and to a primary recrystallization annealing, applying an annealing separator composed mainly of MgO and then subjecting to final annealing, a heating rate S 1 at a zone of 500ˆ¼600°C in a heating process of the primary recrystallization annealing is not less than 100°C/s and a heating rate S 2 at a zone of 600ˆ¼700°C is a range of 30ˆ¼(0.5 x S 1 )°C/s and an oxidation potential P H2O /P H2 of an atmosphere at a zone of 500ˆ¼700°C is preferably not more than 0.05, whereby secondary recrystallized grains are refined over a full length of a product coil to decrease an iron loss. |
