Tribological Dependence of CrSiBCN Composite Coatings on Different Counterparts in Water Lubrication

Abstract

The purpose of this study is to determine the suitable counterpart matching with CrSiBCN coating in water lubrication by comparing the tribological properties sliding against four counterparts. The results showed that the tribological properties of CrSiBCN coatings were not only dependent on the hardness but also on the chemical inertness of counterparts. SiC and GCr15 which could have tribochemical reaction with water presented lower friction coefficient (0.14 and 0.20) than inert Al2O3 and brass (0.24 and 0.35). For the same reason, the wear rates of CrSiBCN coatings sliding against SiC and GCr15 (1.5 × 10–7 mm3/Nm and undetectable) were also lower than CrSiBCN coatings sliding against Al2O3 and brass (8.8 × 10–7 and 1.4 × 10–6 mm3/Nm). On this basis, GCr15 was easy to confront plastic deformation due to low hardness and subsequently resulted in a rough friction interface. It was the reason for GCr15 to present the higher friction coefficient (0.20) than SiC (0.14). SiC was the suitable counterpart material to match with CrSiBCN coating in water by taking into account friction coefficient and wear rate.