Effect of cerium acetate doping on corrosion behavior of sol-gel coatings on 2A12 aluminum alloy

Si-Zr hybrid sol-gel coatings on 2A12 aluminum substrate were prepared, and the effect of cerium acetate (Ce(CH₃COO)₃) doping on corrosion behavior of the sol-gel coatings was examined. The scanning electron microscopy (SEM) was employed to investigate the morphology of the coatings, and the corrosion resistance of the coatings was evaluated by electrochemical methods and neutral salt spray tests. In addition, the structure and the inhibition mechanism of Ce(CH₃COO)₃ doped sol-gel coatings were discussed by Fourier transform infrared (FTIR) analysis. It is indicated that proper doping concentration of Ce(CH₃COO)₃ can effectively improve the corrosion resistance of the sol-gel coatings, while the higher concentration of Ce(CH₃COO)₃ would reduce the homogeneity and stability of the coatings, and further destroy the corrosion protection properties of the coatings.