The influence of CeO2 particle with various sizes on the microstructure and properties of electrodeposited Ni-CeO2 composite coatings

In current work, Ni-CeO2 composite coatings with various CeO2 particle sizes are prepared in Watts bath. The influence of CeO2 particle with various sizes on the microstructure and properties in electrodeposited Ni-CeO2 composite coatings is investigated. When compared to microparticles, nanoparticles exhibit greater benefits in optimizing the surface topography and achieving a more homogeneous coating surface. Furthermore, the nano coatings possess a more random surface grain orientation, a high level of grain refinement, and numerous low angle grain boundaries (LAGB). The analysis of macro and micro textures in coatings unveils that nanoparticles exhibit superior performance in suppressing texture compared to microparticles. Microparticles primarily contribute to the improvement of microhardness in the nickel coating, whereas nanoparticles play a crucial role in ensuring a homogeneous distribution of microhardness. The electrochemical test results indicate that the corrosion resistance of nano coatings surpass micro coatings due to the grain refinement and homogeneous corrosion. Nanoparticles demonstrate a higher efficiency in promoting the formation of NiO and Ni(OH)2 within the coatings compared to microparticles. As a result, the corrosion resistance of the nano coatings is significantly enhanced.