Magnesium Alloy Composite Water‐Repellent Surface with Durable Corrosion Resistance and Self‐Cleaning Behavior

Magnesium (Mg) alloys have poor corrosion resistance, higher requirements for corrosion resistance of the coating, and the changes in the environment in the actual application are complicated and diverse. Therefore, it is urgent to develop bio‐inspired water‐repellent surfaces (WRSs) with long‐lasting corrosion resistance and multiple excellent properties for Mg alloys. In this study, a composite water‐repellent surface (CWRS) with long‐lasting corrosion resistance and self‐cleaning behavior is prepared by combining laser processing, hydrothermal treatment, and immersion method on the Mg alloy surface. The effect of ambient temperature changes on the wettability and corrosion resistance of the CWRS is investigated. The experimental results showed that a uniform and dense CWRS with a film thickness of 36 μm could be prepared on the Mg alloy surface at an ambient temperature of 180 °C, demonstrating excellent corrosion resistance and self‐cleaning behavior. In addition, in the harsh salt spray test, it is found that even if the superhydrophobicity of the CWRS was lost, the surface still has good corrosion resistance. Multifunctional CWRSs have become a research hotspot, and it is of great significance to promote the application of Mg alloys in actual working conditions.