METHOD FOR DEGREASING COLD ROLLED STAINLESS STEEL STRIP

摘要

PURPOSE:To effectively degrease a cold rolled stainless steel strip provided with high strength by cold rolling while improving the rust resistance and surface color tone of the steel strip by heating the steel strip under specified conditions and electrolyzing it in an aqueous nitric acid soln. CONSTITUTION:A cold rolled stainless steel strip provided with high strength by cold rolling is heated to 300-600 deg.C in an oxidizing atmosphere to burn and remove rolling oil sticking to the surfaces of the steel strip. The steel strip is then electrolyzed in an aqueous nitric acid soln. having about 50-200 g/l concn. at about 40-70 deg.C and about 5-15 A/dm<2> current density to vanish temper color formed newly on the surfaces of the steel strip and to remove the combustion residue of the rolling oil. Thus, the rust resistance of the stainless steel strip is improved and the surface color tone can be arbitrarily controlled within a wide range.