Evaluation of Hardness and Tribological Behavior of Ni-B4C-WS2 Hybrid Coating Fabricated by Electrodeposition

The purpose of this study was the co-electrodeposition of boron carbide (B4C) hard particles and tungsten sulfide (WS2) lubricant particles on copper substrate and produce Ni-B4C-WS2 nanocomposite coatings. Hardness and tribological behavior of nanocomposite coatings were also investigated. Field emission electron microscopy (FESEM) was used to study the microstructure of coatings and hardness and tribological behavior, were evaluated by microhardness and pin-on-disk tests respectively. The results showed that hybrid nanocomposite coating is more fine-grained than other coatings, and have a better distribution of boron carbide and tungsten sulfide particles. The hardness of hybrid coating was obtained 461 vickers, which was much higher than that of the other two coatings. The lowest weight loss after wear test at slide distance of 800 m was obtained in 1 mg hybrid coating which was much lower than other two coatings. Also, the lowest friction coefficient for the hybrid coating was 0.53.