Preparation and Friction and Wear Resistance of SiC/Ni Nano-Composite Coatings

Pure nickel coating and SiC/Ni nano-composite coatings were prepared on 316L stainless steel surface by electro-deposition method. The influences of plating time, SiC mass concentration, current density and temperature of plating bath on the SiC content in the composite coatings were studied. The surface morphology of the coatings and the size of SiC nano-particulates were characterized. The friction and wear properties of the the coatings were investigated. The results show that SiC contents in the composite coating first increased and then decreased with increasing the plating time, current density, SiC concentration and temperature of the plating bath; and the optimal technological parameters were as follows: plating time of 30 min, SiC concentration of 20 g·L-1, current density of 2 A·dm-2, bath temperature of 60 ℃, pH of 4.5, stirring rate of 300 r·min-1. The grain size of SiC/Ni nano-composite coatings was smaller than that of the pure nickel coating. Comparing with the pure nickel coating, Ni-SiC nano-composite coatings had better friction and wear resistance, and its friction coefficient and wear rate were reduced by more than 7% and 50%, respectively.