Effect of cerium on the microstructure and anti-corrosion performance of Al-Zn coatings

With the increasing application scope of aluminum alloys in the marine field, exploring the surface anti-corrosion technologies of aluminum alloys is becoming more and more important. In current industries, thermal spraying is generally used to prepare Al-Zn coatings for surface protection. In this paper, Al-Zn coating and Al-Zn-Ce coating were prepared by flame spraying technology, and the effects of adding rare earth element Ce on the microstructure and corrosion resistance of Al-Zn coating were systematically studied by using OM, SEM, XPS, LCSM and electrochemical corrosion tests. The results show that the addition of Ce is conducive to promoting the mobility and solidification shrinkage of Al-Zn alloy melt, thereby increasing the density of the coating while decreasing porosity and roughness. Moreover, adding Ce improves the hardness and wear resistance of the Al-Zn coating. During immersion, adding a trace of Ce to the Al-Zn coating will affect the passivation process and the formation of the passivation film, endowing the coating with a strong passivation ability and thus improving the corrosion resistance of the coating.

Automated summary

In this study, Al-Zn coating and Al-Zn-Ce coating were prepared by flame spraying technology, and the effects of adding Ce on the microstructure and corrosion resistance of the coatings were systematically studied. The results showed that the addition of Ce improved the density, hardness, and wear resistance of the coatings, as well as enhanced their corrosion resistance.