Abstract: A method for producing high magnetic flux density grain oriented electrical steel sheets or strips having a B.sub.8 characteristic in the rolling direction of not less than 1.9 Wb/m.sup.2 by hot rolling, continuous annealing for precipitation of the AlN, cold rolling into the final thickness, decarburization annealing, and finishing annealing. The cold rolling includes a final rolling at a strong reduction between 81 and 95%.

Abstract: Process for producing grain-oriented electric steel sheets having a remarkably improved magnetic flux density, comprising hot rolling silicon steel material containing 0.025 to 0.085% C, 2.0 to 4.0% Si, 0.010 to 0.065% acid soluble Al, continuously annealing the steel at a high temperature between 950.degree. and 1200.degree.C before a final strong cold rolling, rapidly cooling the steel to precipitate AlN, cold rolling the steel by a one-step or two-step cold rolling including a final strong cold rolling with a reduction rate range of 81 to 95% into the final thickness, coating a separating agent on the sheet after a decarburization annealing, and subjecting the sheet to a final annealing to obtain a grain-oriented electric steel sheet having excellent excitation characteristics and B.sub.8 characteristics of at least more than 1.90 Wb/m.sup.2, said separating agent containing 0.1 to 15% of antimony or an antimony-containing compound.

Abstract: A cold rolling method for producing a high magnetic flux density grain oriented electrical steel sheet or strip having remarkably excellent B.sub.8 characteristics, comprising subjecting a hot rolled steel sheet or strip a combination of heavy cold rolling with annealing during which the steel sheet or strip is held at a temperature between 100.degree. and 350.degree.C at an interim sheet thickness stage during the heavy cold rolling.