Improvement of anticorrosion and adhesion to magnesium alloy by phosphate coating formed at room temperature

来源期刊：中国有色金属学报(英文版)2010年第7期

论文作者：牛丽媛 林继兴 李勇 史子木 徐临超

文章页码：1356 - 1360

Key words：anticorrosion; adhesion; magnesium alloy; paint; phosphate coating

Abstract: A new surface protection process was developed to magnesium alloy against corrosion in aggressive environments. Firstly, a phosphate coating was formed on rinsed magnesium alloy. Then, powder painting was carried out on the phosphated magnesium alloy. Surface morphologies and phase compositions of the phosphate coating were investigated by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results show that the phosphate coatings formed in bath containing earth additives at room temperature have dense and fine microstructure. The phosphate coating provides excellent paint adhesion to the magnesium alloy. Salt spray tests indicate that the corrosion resistance of the phosphate coating plus paint could meet the demand of magnesium alloy automobile components in aggressive environments.