温度及酒石酸对5182铝合金硫酸阳极氧化膜结构和耐蚀性能的影响

Effect of Temperature and Tartaric Acid on the Structure and Corrosion Resistance of the Anodic Film Formed on 5182 Aluminum Alloy in Sulfuric Acid Solutions

通过5182铝合金硫酸阳极氧化,研究了温度、酒石酸浓度对阳极氧化膜结构和耐蚀性能的影响。采用扫描电镜观察不同条件下阳极氧化膜的表面结构,通过电化学阻抗谱研究阳极氧化膜的耐蚀性能。结果表明:温度在20~30℃时,随着温度升高,阳极氧化膜膜厚增加,合金的耐蚀性能增强;当温度超过35℃,氧化膜发生溶解,合金耐蚀性能下降。在硫酸溶液中,添加酒石酸能显著提高氧化膜成膜效率,降低氧化膜溶解速率;随着酒石酸浓度的增加,氧化膜膜厚增加,表面孔径减小,合金耐蚀性能增强。

The effect of temperature and tartaric acid additionon to the structure and corrosion resistance of the anodic films formed on 5182 aluminum alloy in sulfuric acid solutions was studied.The morphology of the anodic films was examined using scanning electron microscope.The corrosion resistance of the anodic films was investigated through electrochemical impedance spectroscopy.The results showed that,when the temperature was in the range of 20~30℃,the film thickness and its corrosion resistance increased with the increase of the temperature.When the temperature exceeded 35℃,the oxide film started to dissolve,leading to decline of the corrosion resistance of the anodic film.The addition of tartaric acid to the solution could reduce the dissolution rate of the anodic film and improve the film-forming efficiency.With the increase of tartaric acid concentration,the thickness of the anodic film increased,the pore size decreased,and the corrosion resistance of the anodized alloy increased.