Effect of anodizing time on cracking behavior of anodic oxide film of 2A12 alloy

Anodic oxide film was obtained by different anodizing time. The anodic oxide film was studied by using scanning electron microscopy (SEM), electron probe, continuity test, electrochemical impedance spectroscopy (EIS) and salt spray corrosion tests. It is shown that some cracks present in the sealed anodic oxide film of different oxidation time after the thermal shock, but the cracks hardly penetrate through the film. With the increasing oxidation time, the density of cracks in anodic oxide film increases after the thermal shock. Considering the cracking behavior and corrosion resistance of oxide films on different oxidation, anodic oxide film obtained at 30 min has the best corrosion resistance after the thermal shock.