Preparation and Corrosion Behavior of Fluorine-free Silane Modified Cerium-Oxide Film by CVD Method on the Aluminum Alloy 2024-T3

A cerium-oxide film with flowerlike micro-nanostructure was prepared by hydrothermal method and modified by CVD method with fluorine-free silane (TMOS and MTMS) to obtain super-hydrophobic performance on the surface of aluminum alloy 2024-T3. The films were characterized by scanning electronic microscope (SEM), energy dispersive X-ray spectroscopy (EDX), Fourier transform infrared spectroscopy (FTIR) and electrochemical impedance spectroscopy (EIS). The effect of the reactant ratio, catalyst concentration and CVD time on the hydrophobicity were investigated in detail. The boiling water pretreatment was proved to take structural-oriented effect on growth of cerium-oxide film with flowerlike micro-nanostructure. The results revealed that the cerium-oxide film prepared by boiling water pretreatment was more suitable as a base film. Electrochemical measurements showed that the super-hydrophobic modification of cerium-oxide film significantly improved the anticorrosion property of aluminum alloy, and the stable air layer formed on the modified surface was necessary to the improvement of the corrosion resistance.