FERRITIC STAINLESS STEEL SHEET EXCELLENT IN ADHSION WITH COATING FILM AND ITS PRODUCTION

摘要

PROBLEM TO BE SOLVED: To provide a ferritic stainless steel sheet having a surface form high in adhesion with a coating film by continuous production. SOLUTION: This ferritic stainless steel sheet excellent in adhesion with a coating film is the one in which pits are closely formed on the surface of the steel sheet, and the average diameter D (μm) of the opening parts of these pits and the average depth H (μm) of the pits satisfy the relations in the following inequalities I and II: the inequality I: 1<=D<=5 and the inequality II: D/3<=H<=D/2. The stainless steel sheet can be produced by subjecting a stainless steel to alternating electrolysis of 1 to 10Hz in which the current density in the case of anode electrolysis to 1.0 to 10.0kA/m<2> and that in the case of cathode electrolysis to 0.1 to 3.0kA/m<2> for 10 to 120sec in an aq. soln. of ferric chloride contg. Fe<3+> by 1 to 50g/L.