| 摘要 |
PURPOSE:To improve the slipperiness, heat resistance, etc., of the steel sheet and to obtain the steel sheet having excellent magnetic characteristics by subjecting a silicon steel slab to repetitive rolling and annealing, then applying a coating liquid for forming insulating films under prescribed conditions contg. a colloidal silica liquid, etc., then subjecting the steel sheet to a baking treatment. CONSTITUTION:The silicon steel slab is subjected to hot rolling, annealing, cold rolling, etc., to the final sheet thickness. This material is subjected to decarburization annealing then to final finish annealing. The coating material for forming the insulating films is applied thereon and thereafter, the coating is subjected to heat flattening. The above-mentioned coating material is prepd. by adding 130 to 250, by weight, phosphate of Al, Mg, etc., 10 to 40 chromic anhydride, chromate, etc., and 0.5 to 25 noncolloidal solid of 5 to 200nm particle size as the oxide, carbide, etc., of elements, such as Fe, Ca, and Ba to 100 (as SiO2) colloidal soln. consisting of colloidal silica of 50nm grain size. |
