METHOD FOR FORMING INSULATION FILM ON GRAIN ORIENTED MAGNETIC STEEL SHEET

摘要

PROBLEM TO BE SOLVED: To produce a grain oriented magnetic steel sheet having low iron loss by forming an insulation film imparting high tensile force to the steel sheet thereon. SOLUTION: In the method for forming an insulation film on a grain oriented magnetic steel sheet, a mixed liquid of an alumina sol essentially consisting of a low crystallinity alumina sol, boric acid and nitric acid is used as an insulation film coating liquid. Thus, the stability in viscosity or the like of the insulation film coating liquid can be secured without damaging the tensile force of the insulation film. COPYRIGHT: (C)2004,JPO