Effect of concentration of Ce(NO3)3 · 6H2O and temperature on the corrosion resistance of Al2O3/cerium oxide composite films on 1060 Al alloy

Abstract

In this paper, Al2O3/cerium oxide composite films were prepared on the surface of aluminum by anodic oxidation and chemical solution deposition. The aluminum was firstly anodized in sulfuric acid, then treated with different concentrations of Ce(NO3)3 · 6H2O solution at different temperatures. X‐ray diffraction (XRD), energy dispersive spectrometer (EDS), scanning electron microscope (SEM), electrochemical impedance spectroscopy (EIS), and electrochemical polarization tests were used to characterize the properties of the composite films. The results indicate that the Al2O3/cerium oxide composite films successfully form on 1060 Al alloy, and the best condition of film‐forming is 2 g/L Ce(NO3)3 · 6H2O and 50 °C. Al2O3/cerium oxide composite film under this condition has a uniform, smooth, and pyknotic surface topography and optimal corrosion resistance. The corrosion density at that time is 1.106 × 10−6 A/cm2 and the corrosion potential is −0.458 V.