Enhancing the Corrosion Resistance of ZnAl-LDHs Films on AZ91D Magnesium Alloys by Designing Surface Roughness

Zinc–aluminum layered double hydroxides (ZnAl-LDHs) film is a typical effective corrosion resistant currently being explored. In this study, ZnAl-LDHs was prepared on magnesium alloys with different surface roughness by means of metallographic preparation combined the hydrothermal method. When Sa at minimum 0.094 μm, ZnAl-LDH films grew most intensely, reaching 3.8 μm in thickness static contact angle 84.34° and current density (icorr) 1.12 × 10−4 A/cm2. After neutral salt spray test, sample mass only increased 0.0424 g. The results show that size nanosheets can be tailored Mg alloy surface. low substrate accelerate growth rate films, increase improve their resistance, but it disadvantageous to excellent hydrophobic properties Finally, possible prevention mechanisms LDHs were proposed. This also provides theoretical basis for optimal processing parameters