Influence of boron nitride on tribological behavior of nickel-base composite coatings at high temperature

摘要

The nickel-based boron nitride composite coatings were prepared by reversing pulse electro-deposition. The mechanical properties and friction behavior of the coatings at high temperature were tested by using AI2O3 ceramic ball at high temperature friction-testing machine. The results show that the surface micro-hardness of the coatings increases with the addition of BN powder. Meanwhile, the friction coefficient and wear rate of specimens decreases. Especially when the BN addition is 1.5g/L the composite coatings present a minimum of friction coefficient and wear rate. In optimum process parameters, the friction coefficient of the coatings is about 0.2 at room temperature and 0.4-0.5 at 600°C. In addition, the friction and wear properties were significantly improved by plating Ni transition layer plated between substrate and composite coating.