COMPOSITION AND PROCESS FOR SUBSTITUTIONALLY PLATING ZINCIFEROUS SURFACES

摘要

An acidic substitutional plating bath for zinciferous surfaces, particularly zinciferous metal-plated steel sheet, with which sludge production and equipment corrosion are inhibited and which has an improved heavy metal ion deposition efficiency is provided by an aqueous composition that has a pH of 2 to 4.5 and that contains 1.5 to 40 g/L of at least one heavy metal ion selected from nickel, iron, and cobalt; 0.5 to 10 g/L of phosphate ions; 1 to 250 g/L of sulfate ion; and 1 to 20 g/L of organic acid.