Sliding wear performance of nickel-based cermet coatings composed of WC and Al2O3 nanosized particles

This paper investigates the sliding wear performance of two types of co-electrodeposited cermet coatings composed of nano-sized tungsten carbide (WC) and combined tungsten carbide and alumina (Al2O3) particles incorporated in a nickel matrix. For this purpose, the effects of alternating the ceramic particle concentration in the electrolyte solutions on microhardness of the coatings and also the effect of applied loads on wear performance of the coatings have been studied using ball-on-flat sliding wear tests. The wear track volumes and the progression of wear depths as a function of time and at three applied loads were recorded and wear track morphologies were investigated using FE-SEM and microhardness testing. The results showed that microstructure, microhardness and wear performance of the coatings composed of WC improved when Al2O3 particles were introduced into the matrix. It was also found that the rule of mixtures for composite materials provides a good explanation for microhardness behaviour while Archard equation can explain the changes in wear performance due to the hardness and microstructural changes.