| 摘要 |
In a method for producing a grain-oriented electrical steel sheet by hot rolling a steel slab having a chemical composition comprising C: 0.001ˆ¼0.10 mass%, Si: 1.0ˆ¼5.0 mass%, Mn: 0.01ˆ¼0.5 mass%, Al: less than 0.0100 mass%, each of S, Se, O and N: not more than 0.0050 mass% and the remainder being Fe and inevitable impurities, subjecting the resulting hot rolled sheet to a single cold rolling or two or more cold rollings sandwiching an intermediate annealing therebetween to a final thickness, subjecting to a primary recrystallization annealing, applying an annealing separator thereto and then subjecting to a finish annealing, a zone of 550ˆ¼700°C in a heating process of the primary recrystallization annealing is rapidly heated at an average heating rate of 40ˆ¼200°C/s, while any temperature zone of 250ˆ¼550°C is kept at a heating rate of not more than 10°C/s for 1ˆ¼10 seconds, whereby secondary recrystallized grains are refined to obtain a grain-oriented electrical steel sheet stably realizing a low iron loss. |
