SURFACE-TREATING METHOD FOR ALUMINUM OR IT'S ALLOY

摘要

PURPOSE: A surface-treating method for aluminum or it's alloy is provided, which is able to form a coating layer having excellent corrosion-resistance and peeling-resistance on the surface of the aluminum and it's alloy and decrease the pollution of the environment and reduce the treating cost. CONSTITUTION: A surface-treating method comprises steps of: (i) degreasing aluminum or it's alloy; and (ii) coating the surface of the aluminum or it's alloy with sodium hydroxide solution containing potassium ferrite in a concentration of 1-30 gram/liter, wherein the coating solution further contains 1-10 gram/liter of potassium permanganate and 0.5-10 gram/liter of Na2S2O6 or the coating solution further contains 5-10 gram/liter of NaOCl.