Effect of TiO2 Sol on the Microstructure and Tribological Properties of Cu-Sn Coating

In order to improve the hardness and wear resistance on condition that the self-lubricating property is ensured, Cu-Sn coatings were prepared and strengthened by combining sol-gel method and composite electroplating technology. TiO2 sol was added to the Cu-Sn electroplating bath to obtain nano-particles reinforced Cu-Sn-TiO2 composite coatings. The microstructure, composition, microhardness and tribological properties were analyzed. The results show that the introduction of the TiO2 sol in the plating solution changes the composition and structure of the composite coatings. The co-deposited TiO2 is uniformly distributed in the Cu-Sn matrix and greatly improves the microhardness and tribological properties of the Cu-Sn coating.