TRIBOLOGY OF Fe–CuNiSn AND FeCu–NiSn–VN COMPOSITES OBTAINED BY POWDER METALLURGY METHODS

Abstract

Study results of the mechanical and tribological properties of the Fe-Cu-Ni-Sn and Fe-Cu-Ni-Sn-VN composite materials (nanohardness, elastic modulus, friction force, coefficient of friction, wear) obtained by powder metallurgy methods are presented. It was shown that the use of 3 wt% nano-dispersed VN powder in the 51Fe–32Cu–9Ni–8Sn charge, in which the grain size was ~2000–5000 nm, makes it possible to increase the nanohardness from 2.68 to 5.37 GPa and reduce the elastic modulus from 199 to 125 GPa. As a result, the parameters H/E and H³/E², which describe the resistance of the material to the elastic deformation of failure and the resistance of the material to plastic deformation, increase by 3.3 and 20 times, respectively, and the friction force and the volume of the wear groove decrease by 1.8 and 16 times, respectively. The reasons for the change in the mechanical characteristics of sintered composites during nanoindentation and the different nature of their wear are discussed. The interrelation of the microstructure with mechanical and tribological properties is established. It is shown that the parameters H/E and H³/E² can be used to predict the wear resistance of the composites under study.