Effect of Surface Treatment on Intergranular Corrosion Behavior and Exfoliation Corrosion Behavior of 2E12-T3 Aluminum Alloy

Al alloy 2E12-T3 was separately treated by Al surface-cladding,anodizing and micro-arc oxidation.An immersion corrosion test rig,a metallographic microscope,a scanning electron microscope and an X-ray diffractometer were performed to study the effect of surface treatment on the intergranular corrosion behavior and exfoliation corrosion behavior of the Al alloy.It was found that 2E12-T3 Al alloy was very sensitive to intergranular corrosion and exfoliation corrosion.Al surface-cladding,anodizing and micro-arc oxidizing could all significantly improve the intergranular corrosion resistance and exfoliation corrosion of the Al alloy.Particularly,micro-arc oxi dizing was the most effective in increasing the intergranular corrosion resistance of the Al alloy,while Al surface-cladding was the most effective in increasing the exfoliation corrosion of the Al alloy.