铝基防护层表面铈转化膜的制备与耐蚀性能

Preparation and Corrosion Resistance of Cerium Conversion Coating on the Surface of Aluminum Protective Coating

为了提高铝基防护层的耐腐蚀性能,采用L9(34)正交试验法,优化了铈盐改性溶液的配方,确定了工艺条件,在铝基防护层表面制备了铈转化膜,并考察和比较了铈转化膜的性能指标。通过试验,确定了优化后的转化配方主要成分及工艺:14.0g/LCe(NO3)3,0.3g/L(NH4)2S2O8,0.3mL/L促进剂,pH=1.5～3.0,温度25℃,时间25min。本工艺制备的转化膜耐蚀性优于Alodine1001,能满足飞机高强度钢部附件表面铝基防护层改性处理的要求。

In order to improve the corrosion resistance of aluminum protective coating,Ce conversion coating was prepared on the Al protective coating from a modified Ce salt solution based on L9(34) orthogonal test.The conditions for preparing Ce conversion coating were optimized in relation to the investigation of corrosion resistance.It was suggested that the conversion solution consisted of 14.0 g/L Ce(NO3)3,0.3 g/L (NH4)2S2O8 and 0.3 mL/L accelerating agent.The optimized conversion conditions were suggested as pH value of 1.5～3.0,temperature of 25 ℃ and time of 25 min.Resultant Ce conversion coating had better corrosion resistance than Alodine1001 and was qualified for modification of Al protective coating on the surface of high-strength steel parts of aircrafts.