A protective superhydrophobic Mg–Zn–Al LDH film on Surface-Alloyed Magnesium

A novel approach was developed to fabricate a protective superhydrophobic LDH film on a Zn–Al alloyed surface of AZ31 Mg alloy. The alloyed surface layer not only provided essential divalent and trivalent cations and a base for the direct growth of a Mg–Zn–Al LDH film in a sodium nitrate hydrothermal solution, but also offered additional corrosion and mechanical protection for the substrate magnesium alloy. Further modification with low surface energy lauric acid (LA) could change the micro/nano hierarchical topographic surface of the LDH film from hydrophilicity to super-hydrophobicity. The long-term anti-corrosion performance, super-hydrophobicity, wear resistance, chemical stability and adhesion strength of the LA-modified LDH film on the surface-alloyed AZ31 were experimentally verified.