3种表面处理对2E12-T3铝合金晶间腐蚀和剥离腐蚀行为的影响

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

为了有效控制2E12新型铝合金的晶间腐蚀和剥离腐蚀破坏,对2E12-T3铝合金表面分别进行了包铝、阳极氧化和微弧氧化处理,利用浸泡腐蚀试验、金相显微镜、扫描电镜(SEM)和X射线衍射仪(XRD)等研究了表面处理对2E12-T3铝合金晶间腐蚀和剥离腐蚀行为的影响规律,探讨了作用机理。结果表明:2E12-T3铝合金对晶间腐蚀和剥离腐蚀十分敏感,表面包铝、阳极氧化和微弧氧化均能显著提高2E12-T3铝合金的抗晶间腐蚀和抗剥离腐蚀性能,其中微弧氧化处理提高抗晶间腐蚀性能的效果最好,表面包铝提高抗剥离腐蚀性能的效果最好。

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.