METHOD FOR MAINTAINING A FLUX SOLUTION OF THE MELTED ZINC PLATING PROCESS AND ZINC PLATING PROCESS USING THE METHOD

摘要

PURPOSE: A method for maintaining a flux solution of the melted zinc plating process and a zinc plating process using the method are provided, for prolongation the lifetime of a flux solution, and for omitting the washing step in the zinc plating process to reduce the amount of waste water and sludge. CONSTITUTION: A flux solution is maintained by adding hydrogen peroxide and liquid ammonia into a flux solution to make the pH be 3.0-4.5 and to remove the acids and the iron components contained in the flux solution. The flux solution contains zinc chloride and ammonium chloride in the ratio of 1: 1 to 1: 4. The melted zinc plating process comprises the steps of removing the fat from the surface of the substrate to be plated; washing the substrate; pickling the substrate; soaking the substrate into the flux solution which is maintained by the above mentioned method; plating the substrate; and cooling the substrate.