Dry sliding friction and wear behaviour of developed copper metal matrix hybrid composites

Abstract

In the present investigation, dry sliding friction and wear behaviour of developed copper-based hybrid composites were studied. Tungsten carbide (WC), zirconia (ZrO2), alumina (Al2O3) of grade A6 and chromium (Cr) hybrid reinforcements were utilised to develop various copper-based hybrid composites using liquid stir-casting technique. The developed hybrid composites were characterised by X-rays diffraction (XRD), high-resolution scanning electron microscope (HR-SEM), energy-dispersive analysis of X-rays (EDAX), relative density and Vickers hardness. Developed hybrid composites show improved Vickers hardness compared to its copper matrix while relative density was found lower. Dry sliding friction and wear behaviour of the developed hybrid composites were studied using pin-on-disc tribometer at variable normal load, constant sliding speed and sliding distance. Hybrid composites exhibited low wear compared to its copper matrix, particularly (WC + Al2O3 + Cr) hybrid reinforced composites revealed better wear resistance among all. Fluctuating nature of the coefficient of friction was observed in all the materials. However, developed hybrid composites revealed higher coefficient of friction compared with its matrix. The worn surfaces were analysed using scanning electron microscopy (SEM), EDAX and optical profilometer to discuss the friction and anti-wear mechanism involved in developed materials.