| 摘要 |
A process for producing a grain -oriented electromagnetic steel sheet the process comprising hot rolling a steel slab that contains, in terms of mass% , 0.001- 0.20% C , 1.0 -5.0% Si, 0.03 -1.0% Mn , 0.005- 0.040% S and/or Se , 0.003 -0.050% sol. Al, and 0.0010 0.020% N , cold -rolling the sheet to a final sheet thickness, subjecting the sheet, to primary recrystallization annealing, thereafter applying an annealing separator that comprises MgO as the main component , and subjecting the coated sheet to final finish annealing wherein the rate of heating S from 500ºC to 600ºC and the rate of heating S from 600ºC to 700ºC during the heating in the primary recrystallization annealing are regulated to 100 ºC/s or higher and a value in the range of 30- (0.5×S) ºC/s , respectively. Preferably the atmosphere for 500- 700ºC is regulated so as to have an oxidation potential P/P of 0.05 or less. Thus, the product coil is made to have finer secondary -recrystallization grains throughout the entire length thereof and have a reduced core loss. |
