Quantification of corrosion mechanisms under immersion and salt-spray environments on an extruded AZ31 magnesium alloy

Abstract The corrosion mechanisms of pitting, intergranular, and general corrosion were examined on an extruded AZ31 magnesium alloy subjected to immersion and salt-spray environments. The three mechanisms were quantified using optical microscopy and laser profilometry for over 60 h of testing. Although both environments showed similar trends, the immersion environment was more deleterious with respect to intergranular and general corrosion. On the other hand, the salt-spray environment did allow deeper pits to form throughout the entirety of the experiments, which then led to a substantial thickness drop (general corrosion) compared with the immersion environment.