Inhibitive effect of sodium carbonate on corrosion of AZ31 magnesium alloy in NaCl solution

Abstract Magnesium is the world’s lightest structural metal, with a significant growth potential in view of the accelerating demand for light-weighting portable devices and transportation (aerospace, automotive), amongst other. The effect of carbonate ions on corrosion protection of AZ31 magnesium alloy was studied in 0.1 M NaCl solution saturated in Mg(OH)2 using Electrochemical Impedance Spectroscopy (EIS), potentiodynamic polarization measurements, hydrogen evolution tests and SEM-EDX analysis. X-ray Photoelectron Spectroscopy (XPS) was used in order to investigate the top-surface composition. The inhibitive effect of CO32- ions on corrosion of AZ31 magnesium alloy was highlighted and the underlying mechanisms discussed.