| 摘要 |
PURPOSE:To develop the grain oriented electrical steel sheet having an extremely good blanking property by previously subjecting the steel sheet surface to inorg. coating then to flattening annealing followed by org. or mixed org. and inorg. coating at the time of subjecting the electrical steel sheet to the flattening annealing. CONSTITUTION:The electrical steel slab contg. <4.0% Si is hot rolled and is subjected to 1 pass or >=2 passes of cold rolling including intermediate annealing to a final sheet thickness. The steel sheet is then subjected to decarburization annealing and finish annealing. The steel sheet is in succession coated with phosphoric acid, aluminum phosphate or other inorg. coating at, for example, 0.5 to 2.5g/m<2> in order to improve the blanking property of the electrical steel sheet having metallic gloss and is then subjected to the flattening annealing at 800 to 870 deg.C. The org. insulating coating of an acrylic system, styrene, polyvinyl, etc., or the coating formed by mixing the inorg. coating with such org. coating is applied on the steel sheet and is baked, by which the electrical steel sheet having a surface insulating characteristic and the extremely good blanking property is obtd. |
