| 摘要 |
PURPOSE:To improve magnetic characteristics, and to ensure a change into the ultra-low loss of a unidirectional silicon steel plate advantageously by using an extremely thin tension film without employing a forsterite foundation film. CONSTITUTION:An silicon steel slab, which contains 0.01-0.06wt% C, 2.0-4.0wt% Si, 0.01-0.20wt% Mn, 0.005-0.20wt% Sb and one kind or two kinds of S and Se at 0.005-0.1wt% in total and the remainder thereof substantially consists of Fe, is hot-rolled, and changed into a cold-rolled plate in final plate thickness through cold rolling, primary recrystallization annealing functioning as decarburization in combination is executed, an annealing separating agent mainly comprising MgO is applied onto the surface of the steel plate, finishing annealing is executed, and secondary recrystallized grains are developed. A forsterite film on the surface of the steel plate is removed, and an extremely thin tension film composed of at least one kind selected from a nitride and/or a carbide or Ti, Zr, etc., an oxide of Al, Si, etc., a boride of Si, Ti, etc., an silicide of Mo, W, etc., a phosphide of B and Si and a sulfide of Fe and Zn firmly applied onto the surface of the steel plate through a mixed phase with Fe i the steel plate is formed. |
