Electrochemical Investigation of the Galvanic Corrosion of AM60 and AD62 Magnesium Alloy in 0.1 M NaCl Solution

The corrosion behaviour of AM60 and AD62 magnesium alloy in 0.1 M NaCl solution was investigated by potentiostatic polarisation measurements. The microstructure was evaluated using XRD and SEM. Cathodic hydrogen evolution, NDE, anodic dissolution of magnesium, the formation of magnesium hydride and possibly aluminium hydride were all restrained with Cd addition (AD62 alloy). The presence of Cd in AD62 alloy suppresses the micro-galvanic couple effect existing between alpha and secondary phases in the alloy, and increases the polarisation resistance arising from the sum effect of the reduced current densities of all anodic and cathodic reactions.