Patent ID: 6929704
Filing Date: 2005-08-16
Classification: C21D,C22C,H01F

Abstract:
1. A method for producing a grain-oriented electromagnetic steel sheet having a low iron loss and excellent strain resistance and performance: forming a hot band for grain-oriented electromagnetic steel containing about 0.010 to 0.120 wt % of C, 1.5 to 7.0 wt % of Si and about 0.03 to 2.5 wt % of Mn, which contains one or more elements selected from the group consisting of Al, B, Sb, Bi and Te in a proportion of about 0.005 to 0.060 wt % in the case of Al, Sb or Te, about 0.0003 to 0.0025 wt % in the case of B and about 0.0003 to 0.0090 wt % in the case of Bi, as inhibitor components, into a final thickness of said sheet by one time cold rolling or by twice or more cold rolling with intermediate annealing with a reduction of 80 to 95% during the final cold rolling after applying, if necessary, annealing said hot band; annealing the steel sheet under conditions conducive to primary recrystallization; applying a multiplicity of dispersed dotted strains, each dotted strain having a diameter of about 0.1 to 4.5 mm, to a surface of said steel sheet after secondary recrystallization and finish annealing; and generating dispersed fine grains having a diameter of about 3mm or less by annealing at a temperature of about 700° C. or more after applying the dotted strains.