Mechanical and Wear Properties of Functionally Graded Cu-11Ni-4Si/ Graphite Composite

Abstract

The key objective of the paper is to investigate the mechanical and wear Properties of functionally graded copper composite (Cu–11Ni–4Si) reinforced with 10 wt% graphite synthesised using stir casting followed by horizontal centrifugal casting technique. Microstructural analysis conducted radially from outer surface exhibited an increasing gradient of particle distribution and maximum hardness of 195 HV was observed at inner surface. Tensile strength of outer and (1–8 mm) and inner zone (9–15 mm) was determined and failure mechanism was analysed. Mechanical tests revealed better properties at inner surface and wear resistance of this layer was analysed using pin-on-disc tribometer based on Taguchi’s L27 orthogonal array with three process parameters, applied loads (10, 20 and 30 N), sliding velocities (1, 2 and 3 m s−1) and sliding distances (500, 1000 and 1500 m). Optimum parameters were identified and confirmation of experiments was carried out. Worn surface was analysed using Scanning Electron Micrograph and oxide layer formation was noticed at increased velocities which enhanced wear resistance.