Environmentally friendly anodization on AZ31 magnesium alloy
(Ningbo Institute of Materials Technology and Engineering, Chinese Academy of Sciences, Ningbo 315201, China)
Abstract: A novel anodization which is environmentally friendly, low voltage and low energy consumption was developed to improve corrosion resistance of AZ31 magnesium alloy. The corrosion resistance of the anodic films was studied by electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques. The microstructure and compositions of films were examined by SEM, XPS and XRD. A new kind of organic additive used in the electrolyte is friendly to the environment. The compact, intact and uniform coating with high hardness can be prepared on AZ31 magnesium alloy by the environmentally friendly anodization, which enhances the corrosion resistance of AZ31 Mg alloy significantly.
Key words: magnesium alloy; corrosion; anodization; environmentally friendly