Effect of La2O3/CeO2 particle size on high-temperature oxidation resistance of electrodeposited Ni-La2O3/CeO2 composites
(1. College of Materials Science and Engineering, Heilongjiang University of Science and Technology,
Harbin 150022, China;
2. College of Materials Science and Engineering, Harbin University of Science and Technology,
Harbin 150040, China)
Harbin 150022, China;
2. College of Materials Science and Engineering, Harbin University of Science and Technology,
Harbin 150040, China)
Abstract: Ni-La2O3/CeO2 composite films were prepared by electrodeposition from a nickel sulfate bath containing certain content of micrometer and nanometer La2O3/CeO2 particles. The effect of La2O3 or CeO2 particle size on the oxidation resistance of the electrodeposited Ni-La2O3/CeO2 composites in air at 1000 °C was studied. The results indicate that, compared with the electrodeposited Ni-film, Ni-La2O3/CeO2 composites exhibit a superior oxidation resistance due to the codeposited La2O3 or CeO2 particles blocking the outward diffusion of nickel. Moreover, compared with nanoparticles, La2O3 or CeO2 microparticles have stronger effect because La2O3 or CeO2 microparticles also act as a diffusion barrier layer at the onset of oxidation.
Key words: Ni-based composite; electrodeposition; high-temperature oxidation; La2O3; CeO2; reactive element effect; oxidation mechanism