SURFACE TREATMENT OF MAGNESIUM OR MAGNESIUM ALLOY

摘要

PROBLEM TO BE SOLVED: To provide a method of surface treatment excellent in corrosion resistance and adhesion with respect to a magnesium metal or its alloy being extremely light in weight and having strength but being seriously subject to corrosion. SOLUTION: An oxide ceramic film is formed on a magnesium metal or magnesium alloy by means of plasma chemical anodic oxidation, and a cationic electrodeposition coated film is formed on the oxide ceramic film. This procedure can provide surface treatment finish producing excellent mechanical strength and superior spread of electrodeposition coating. Further, the corrosion resistance of an oxide film can be improved and a uniform coated film can be produced by forming the cationic electrodeposition coated film after applying surface adjusting treatment to the oxide ceramic film.