目的 进一步改善 6063 铝合金表面 Ce-Mn 转化膜的综合性能。 方法 采用以 Ce(NO3 )3 和KMnO4 为主盐的转化液,在 6063 铝合金表面制备出 Ce-Mn 转化膜,再利用钼酸钠溶液进行后处理,优化处理工艺,获得 Ce-Mn/ Mo 复合转化膜。 对后处理前后的转化膜形貌、成分及电化学性能进行对比,并通过空气中放置、磨损测试的方法对比它们的耐候性和耐磨性。 结果 较优的成膜工艺为:18 g/ L Na2MoO4,1. 5 g/ L 十二烷基苯磺酸钠,成膜时间 18 min,成膜温度 45 ℃ 。 经后处理后,膜层颜色由金黄色转变为棕黑色,组织致密,主要由 Ce,Mn,Mo,O 和 Al 等元素组成,厚度提高至约 7 μm,腐蚀电流密度降低了约 85% 。 结论 与 Ce-Mn 膜层相比,Ce-Mn/ Mo 复合转化膜具有更优异的耐蚀性、耐候性和耐磨性。

Objective To improve the comprehensive properties of the Ce-Mn conversion coating deposited on 6063 aluminum alloy. Methods The Ce-Mn conversion coating was firstly prepared in the solution mainly containing cerium nitrate and potassium permanganate. After that, the Ce-Mn coating was post-treated in the molybdate solution, the treatment processes were optimized, a novel Ce-Mn/ Mo composite conversion coating was formed and its microstructure and properties were characterized. Results The optimal film formation process parameters were as following: Na2MoO4 18 g/ L, sodium dodecyl benzene sulfonate(SDBS)1. 5 g/ L, conversion time 18 min, deposition temperature 45 ℃. After post-treatment, the color of the Ce-Mn coating changed from golden yellow to brownish-black. The test result showed that the Ce-Mn/ Mo composite coating was uniform and dense tissue. This coating was mainly composed of Ce, Mn, Mo, O and Al elements, and the thickness of Ce-Mn/ Mo composite conversion coating was significantly increased to about 7 μm. The corrosion current density was reduced by about 85% . Conclusion Compared with the CeMn coating, the Ce-Mn / Mo composite coating exhibited excellent corrosion resistance, weatherability and wear resistance.