Investigations on the Tribological Properties of Heat-Treated Copper Composite Using Hybrid Quadratic–Radial Basis Function Model

Abstract

This research investigates the effect of heat treatment on mechanical and tribological properties of Cu–11Ni–4Si—10 wt% B4C functionally gradient composite, which is fabricated by the centrifugal casting method. The cast specimens are solutionized at 700 °C for 90 min, followed by air quenching/water quenching. The specimens are artificially aged at different temperatures (500 °C, 550 °C, and 600 °C) and time (1 h, 2 h, and 3 h). The optimum heat treatment condition is established based on the microstructure, microhardness, and tensile strength. The specimens that are heat-treated at optimum condition are subjected to tribological tests by varying the load between 15.8 and 44.44 N and sliding velocity between 0.8 to 2.2 m/s for a sliding distance of 1000 m and 1500 m. The surface morphology and topography of the worn surface are analyzed using FESEM and AFM, respectively. The influence of load and sliding velocity on the wear rate of the specimens is explored using the mathematical models, which are developed using a hybrid polynomial–radial basis function. The results indicate that the load has a direct influence on the wear rate, while the wear rate follows crest parabolic pattern with an increase in the sliding velocity.