Method of producing uniform, fine nickel flash-plated steel sheet for attaching the nickel throughout the steel plate

摘要

PURPOSE: A method of manufacturing a nickel flash plating steel sheet is provided to improve phosphate processing by adhering nickel equally from all of the portions of a steel sheet in plating the nickel. CONSTITUTION: A nucleus of zinc is extracted former than nickel from the rim of a steel sheet(10) where many electric currents flow by adding a small amount of zinc ions to a plating liquid. Thus, the adhered amount of nickel is reduced. The plating liquid contains 3-20g/l of nickel, 5-30g/l of SO4(-2) irons and 0.1-0.8g/l of zinc irons. In plating, the plating liquid has acidity of 4-7pH and keeps over 60°C. The density of electric currents is 3-10A/dm2 in plating and a plating steel sheet with 8-18mg/m2 of nickel adhering amount is obtained.