研制了一种新型的铝合金Ce-Mo基转化膜工艺——AM工艺。此种工艺的成膜溶液组成为：(NH4)2Ce(NO3)6 2.5g/L, NaKC4H4O6*4H2O 2.5g/L, Na2CO3 7.5g/L, Na2MoO4 5.0g/L。铝合金浸在沸腾的此种成膜溶液中20min, 可形成约3.6μm厚的铝合金Ce-Mo基转化膜。于5% NaCl溶液中进行的极化曲线测试和浸泡试验表明，对LF6铝合金，经AM工艺处理形成的转化膜其抗局部腐蚀能力超过了传统的铝合金铬酸盐转化膜。但对LC4铝合金，此种转化膜的耐蚀性能不理想。EDAX和SEM分析表明，LF6和LC4两种铝合金上形成的AM转化膜主要由Al，Ce，Mo的氧化物或氢氧化物组成，但它们的表面形貌差异很大。
A new type of process for forming Ce-Mo based conversion coatings on Al-alloys was developed. Conversion coatings about 3.6μm thickness were obtained by immersing Al-alloys in boiling film formation solution containing (NH4)2Ce(NO3)6 2.5g/L, NaKC4H4O6*4H2O 2.5g/L, Na2CO3 7.5g/L and Na2MoO4 5.0g/L for 20 minutes. In the case of LF6 alloy, polarization curves and immersion tests in 5% NaCl indicated that the conversion coatings exhibited more excellent resistance to localized corrosion than the conventional chromate conversion coatings. However, its resistance to localized corrosion was not satisfactory on LC4 Al alloy. Energy dispersion analyzer of X-ray (EDAX) analysis revealed that the conversion coatings formed on LF6 and LC4 Al-alloys consists mainly of oxides and hydroxides of Al, Ce and Mo. However, their surface microstructure was quite different, which might be contribution to explain their difference in corrosion inhibition.
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