Wear behaviour of the Ni-Cu alloy hybrid composites processed by sand mould casting
J. Kumaraswamy, K.C. Anil, Vidyasagar Shetty, C. Shashishekar
Abstract
Hybrid Metal Matrix Composites are rising in demand to satisfy advanced technological applications due to their improved mechanical and wear properties. In the present work, a sand moulding process is used to develop the Ni-Cu alloy hybrid metal matrix composites (HMMCs) reinforced with aluminium oxide (Al2O3) and titanium dioxide (TiO2) particles. According to ASTM standard, the fabricated Ni-Cu alloy HMMCs undergo microstructure and tribological evaluation. In this study, tribological properties like wear and coefficient of friction analysis are performed on a pin-on-disc wear testing machine with varying (200, 300 and 400 rpm) speeds (20, 30 and 40 N), loads (1 m/sec), sliding velocity. Micrographic images show fairly uniform distribution of the reinforced elements Al2O3 and TiO2 in the Ni-Cu alloy matrix. An analysis of EDS and XRD reveals the presence of reinforced particulate matter in the Ni-Cu alloy matrix. The wear rate of hybrid composites (0.000366 mm3/N-m) is found to decrease (25%) with an increase in 9 wt. % of TiO2/Al2O3 reinforcement when compared to the base alloy (0.000828 mm3/N-m). It can be observed that the addition of Al2O3 and TiO2 particulates in the base alloy nickel, it’s reduced the co-efficient of friction (0.78) at various loads and speeds.