己二酸铵对7075-T6铝合金硫酸阳极氧化的影响

Effects of ammonium adipate on sulphuric acid anodizing of 7075-T6 aluminum alloy

研究硫酸电解液中添加己二酸铵对7075-T6铝合金阳极氧化的影响,采用场发射扫描电子显微镜(FE-SEM)对7075-T6铝合金在不添加和添加己二酸铵的硫酸电解液中制备的阳极氧化膜表面的微观形貌进行分析,采用线性阳极极化研究7075-T6铝合金在两种电解液中的极化行为。利用动电位极化技术和电化学阻抗谱(EIS)研究两种电解液中制备的阳极氧化膜的耐腐蚀性能。结果表明:硫酸电解液中添加己二酸铵可以通过降低电流密度来改善氧化膜的结构,减少氧化膜缺陷,降低微孔孔径,提高阻挡层厚度,从而降低氧化膜的自腐蚀电流密度,提高氧化膜耐腐蚀性能。

The effect of ammonium adipate on the sulphuric acid anodizing of 7075-T6 aluminum alloy was studied.The surface morphologies of anodic oxide films formed in the sulphuric acid solutions with and without ammonium adipate were studied by using field emission scanning electron microscopy(FE-SEM).The anodizing behavior of 7075-T6 aluminum alloy was investigated under linear polarization conditions in sulphuric acid anodizing solutions with and without of ammonium adipate.The potentiodynamic polarization and electrochemical impedance spectroscopy(EIS) were used to study the corrosion resistance of the anodic oxide films formed in the presence and absence of ammonium adipate.The results show that the ammonium adipate in sulfuric acid solution can reduce the cavity defects of the films,decrease the pores diameter,reduce the corrosion current density,enhance the thickness of the barrier layer and improve the corrosion resistance of anodic oxide films by decreasing the current density.