| 摘要 |
This method for producing a grain-oriented electrical steel sheet comprises a series of steps in which a steel material containing, in mass%, 0.002 to 0.10% carbon, 2.0 to 8.0% silicon, and 0.005 to 1.0% manganese, is hot rolled, and hot-rolled sheet annealing is implemented as necessary; then, cold rolling is conducted to produce a cold-rolled sheet of a final thickness; primary recrystallization annealing that doubles as decarburization annealing is implemented; an annealing separation agent is applied to the steel sheet surface; and finish annealing is implemented. A grain-oriented electrical steel sheet with low iron loss and little variation in iron loss values is obtained by: rapidly heating the steel sheet at 50°C/second or higher over an interval of 200 to 700°C, and keeping the steel sheet at any temperature between 250 and 600°C within the aforementioned interval for 1 to 10 seconds, in a heating process for the primary recrystallization annealing; and keeping the temperature within a range of 750 to 900°C, time within a range of 90 to 180 seconds, and PH20/PH2 of the atmosphere within a range of 0.25 to 0.40, in a soaking process for the primary recrystallization annealing. |
