在热浸镀纯铝的工艺条件下，通过在铝液中加入Zn、In、Sn等合金元素，制备了3种阳极性铝合金镀层：Al–5%Zn–0.02%In、Al–4%Zn–0.06%Sn及Al–5%Zn–0.06%Sn。使用光学显微镜、3.5% NaCl全浸腐蚀试验及电化学工作站检测了所得铝合金镀层的组织及性能，并与纯铝、纯锌及55%Al–43.4%Zn–1.6%Si镀层进行了对比。结果表明，镀层的最佳组成分别为Al–5%Zn–0.02%In和Al–(4%~5%)Zn–0.06%Sn。在3.5% NaCl溶液中，其耐蚀性优于55%Al–43.4%Zn–1.6%Si镀层，而腐蚀电位相当；在Cl–浓度为零时未发生铁铝极性逆转，镀层的显微组织与纯铝镀层相同。该热浸铝合金镀层的热浸镀工艺与热浸镀铝完全相同，使用热浸镀铝的设备及工艺即可实现工业生产。%Three kinds of anodic aluminum alloy coatings i.e. Al–5%Zn–0.02%In, Al–4%Zn–0.06%Sn, and Al–5%Zn–0.06%Sn were prepared under process conditions of hot-dip aluminizing by adding Zn and In or Sn alloying elements to aluminum bath. The microstructure and properties of the aluminum alloy coatings were studied by optical microscope, 3.5% NaCl immersion corrosion test, and electrochemical workstation, and compared with that of hot-dip pure aluminum, pure zinc, and 55%Al–43.4%Zn–1.6%Si coatings. The results indicated that the optimized alloy coating compositions are Al–5%Zn–0.02%In and Al–(4%-5%)Zn–0.06%Sn. They showed better corrosion resistance than a 55%Al–43.4%Zn–1.6%Si coating in 3.5% NaCl solution, while having a similar corrosion potential. When the concentration of Cl– is zero, the polarity reversal of iron and aluminum does not occur and the microstructures of the coatings are the same as pure aluminum coating. The hot-dip process of the aluminum alloy coatings is identical with that of the pure aluminum coating, which makes it possible to realize industrial production using the equipments and process of common hot-dip aluminizing.
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