| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide an electromagnetic steel sheet with an insulation film superior in tension pad resistance, and a manufacturing method therefor. SOLUTION: The steel sheet has a mean thickness (Xμm) of an insulation film and a standard deviation of the film thickness (σ) satisfying the expressions (1) and (2): 0.1<=X<=1.5...(1), and 0<=σ/X<0.25> <=0.25...(2). The manufacturing method comprises applying a chemical liquid in which at least one inorganic component selected among chromate, dichromate, phosphate, polyphosphate, silicate, or silicon dioxide, or a mixture of the above inorganic components, and organic components (resins such as epoxy base, or melamine base) are dissolved or dispersed, on the surface of the steel plate, and then drying it at an average temperature-raising speed until the sheet temperature reaches 200 deg.C, of 25 deg.C per second, with a maximum reaching sheet-temperature (T) of 200-400 deg.C, for a drying time (t) of 10-120 seconds.</p> |
