ELECTROLYTE SOLUTION FOR ANODIZING AND CORROSION-RESISTING COATING METHOD OF MAGNESIUM ALLOY USING THE SAME

摘要

PURPOSE: To provide a corrosion resisting coating method for improving corrosion resistance of magnesium alloy more efficiently, environmentally friendly and economically by offering anodizing process of high voltage and low temperature using an economic efficiency improved electrolyte solution, and an electrolyte solution used in the method. CONSTITUTION: The electrolyte solution comprises 100 to 150 g of sodium silicate, 20 to 25 g of potassium acetate and 100 to 150 g of sodium hydroxide on the basis of 1 L of the total aqueous solution, wherein the electrolyte solution further comprises 8 to 12 g of borate, 4 to 8 g of phosphate or both thereof on the basis of 1 L of the total aqueous solution, and wherein the borate is sodium metaborate, and the phosphate is trisodium phosphate. The corrosion resisting coating method comprises a step (1) of alkaline washing the magnesium alloy sample by dipping a magnesium alloy sample (1) into a strong alkali solution of pH 11 or more; and a step (2) of anodizing the magnesium alloy sample in an electrolyte solution containing potassium acetate as hydroxide, silicate solution and carboxylate by connecting the anode (2) to the washed magnesium alloy sample, wherein the anodizing step is performed by connecting the anode to the magnesium alloy sample, using a stainless steel, copper, lead or magnesium substrate as the cathode (3) and flowing a certain current to both ends of the anode and the cathode.