| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for producing a grain-oriented silicon steel sheet remarkably low in iron loss and high in an occupying volume rate in which the surface is provided with an aluminum borate-contg. oxide film having excellent adhesion and smoothness and therefore applying good appearance and tension higher than heretofore to the steel sheet. SOLUTION: The surface of a grain-oriented silicon steel sheet after finish annealing is coated with a fine particle-dispersed soln. contg. an alumina sol in which primary particles have a planar shape representatively by fig (a), an alumina sol. composed of particles with a rod shape, an acicular shape, a feathered shape or the like having >=3 aspect ratio representatively by fig (b) and boric acid, which is dried and gelatinized to form an oxide film. |
