Effect of CeO2 on the Isothermal Oxidation of Electrode-posited Ni-Al Composite Coatings at 950 °C

Electrodeposited Ni-Al and three sorts of Ni-Al-CeO2 composite coatings with different contents of Al were prepared by co-deposition of Ni matrix with Al microparticles and/or CeO2 nanoparticles. The Al microparticles were in a size range of 1∼5 μm, and the CeO2 nanoparticles in an average size of 10 nm. SEM/EDAX and TEM results indicate that CeO2 addition can refine the Ni-Al composite. Oxidation at 950 °C indicates that the addition of CeO2 improve the oxidation resistance at a suitable amount of Al particles in such composites, no matter whether the Ni-Al composite forms NiO or Al2O3 scale. The effect of CeO2 on the oxidation behavior of the electrodeposited Ni-Al composite coatings was discussed.