The effect and mechanism of amion acid on the anodic oxidation of magnesium alloy

Abstract:

To further improve the quality and performance of oxidation film，AZ31 magnesium alloy were anodized in NaOH Na2SiO3 base electrolyte with different aminoacetic acid as organic additives. The effects of different amino acids on the thickness, morphology, structure and corrosion resistance of anodizing films were investigated. The mechanisms of organic amino acids additives were discussed. Results show that there are different effects on the anodizing of magnesium alloy after adding different amino acids in electrolyte. EDTA and L-Orn have remarkable effect on arc restraining, which resulted in an increase in the thickness of anodizing films and a decrease in the surface micro-hole size and porosity, and finally the improvement in corrosion resistance. Organic additives, mainly through the combined effect of inhibition, arc suppression, and surfactant, affect the anodizing process and the performance of oxide film.