Method for coating passivated layer on magnesium and magnesium alloy with excellent anti-corrosion

摘要

A method for coating a passivated layer on magnesium alloy is provided to realize environment-friendly and economical surface treatment by not using chromium at all. A method for coating a passivated layer on magnesium alloy includes the steps of dipping magnesium or magnesium alloy(40) in a composition(10) including cerium(Ce) 0.1~5 mol/l, zinc(Zn) 0.01~1mol/l, and hydrofluosilicic acid(H2SiF6) 0.2~0.4wt%, and coating the magnesium or magnesium alloy with passivated film by applying a pulse voltage from a pulse generator(20).