Preparation and properties of Ni/nano-Al2O3 composite coatings by automatic brush plating

Ni/nano-Al2O3 composite coating was fabricated by automatic brush-plating technique and manually plated Ni/nano-Al2O3 composite coating was also prepared as a comparison. The surface morphology, microstructure, microhardness and wear resistance performance of the coatings were investigated. The results showed that the automatically plated Ni/nano-Al2O3 composite coating possessed smoother, finer, denser microstructure and more uniform performance as compared to the manually plated Ni/nano-Al2O3 composite coating. The former exhibited higher microhardness and better wear resistance under lubricant condition compared with that of the latter. The results presented herein lay the groundwork for future systematical studies in producing nanocomposite coating by brush-plating technique in order to optimize mechanical and tribological properties.