Preparation, microstructure and tribological properties of nano-Al2O3/Ni brush plated composite coatings

Nano-Al2O3/Ni brush plated composite coatings were prepared by co-deposition of Al2O3 nanoparticles with Ni metal matrix during brush plating. In this process nanocrystalline ceramic powders with grain sizes below 40 nm were suspended in the plating solution and deposited with the metal to produce nanoparticle strengthened metal matrix composite coatings. The microstructure, composition, microhardness and wear properties of the coating in abrasive contaminant lubrication were examined. The results show that the nanoparticles are uniformly distributed in the composite coating, and the microstructure of the composite coating is much finer and denser compared with the pure nickel plating coating. Moreover, the microhardness and tribological properties of the composite coating are higher than that of the pure nickel coating.