铝合金阳极氧化膜双向脉冲封闭工艺

研究了一种采用双向脉冲电源将铝合金阳极氧化膜在硫酸铝溶液中进行封闭的绿色工艺。通过正交试验得到了最佳的工艺条件，测试了阳极氧化膜在不同pH值的1mol/L NaCl溶液中的极化曲线，并与沸水封闭、重铬酸钾封闭、氟化镍封闭进行了对比。结果表明，经双向脉冲封闭过的阳极氧化膜可以通过500h的中性盐雾试验，其耐蚀性与传统封闭方法效果相当，有望替代重铬酸盐封闭，并且该封闭工艺适用于处理实验所用含不同元素的铝合金。

A pulse current sealing method for an anodic film on aluminum alloy

A new pulse sealing treatment, involving the use of an asymmetric pulse power supply to seal the anodic film on an Al substrate immersed in a solution of aluminum sulfate, has been developed. Potentiodynamic polarization was employed in order to compare the performance of the new method with other methods, including boiling water sealing, potassium dichromate sealing and nickel fluoride sealing, in corrosion inhibition of anodic oxide films in neutral, acidic and basic solutions of 1 mol/L NaCl. Pulse sealing made the anodic film more uniform and provided the same corrosion resistance as traditional potassium dichromate sealing and can thus provide a green alternative to this environmentally hazardous process. The oxide film sealed by the pulse method was unaffected by a 500 h neutral salt fog test.