| 摘要 |
PROBLEM TO BE SOLVED: To provide a method of manufacturing a grain oriented silicon steel sheet having high Goss integration degree and superior iron loss, on the assumption that a low temperature slab heating - nitriding process is used. SOLUTION: The grain oriented silicon steel sheet can be manufactured by subjecting a silicon steel slab, having a composition consisting of, by weight, 0.02-0.10% C, 2.5-4.0% Si, 0.05-0.45% Mn, <=0.015% S and/or Se, 0.020-0.035% acid-soluble Al, 0.0035-0.012% N, and the balance Fe with inevitable impurities, to heating to <=1280 deg.C and to hot rolling, annealing the resultant hot rolled plate, applying cold rolling at >=80% draft, and then subjecting the resultant sheet to decarburizing annealing, nitriding treatment, and finish annealing. In this case, the average grain size of non-transformed ferritic phases in the annealed hot rolled plate is controlled to 28-85 μm (preferably 35-65 μm). Further, according to Si content (%), C content (%) is regulated to a value within the range satisfying 0.023×Si(%)-0.032-<=C(%)<=0.025×Si(%)-0.010. |
