Wear and friction behavior of copper based nano hybrid composites fabricated by spark plasma sintering

Abstract

Tribological behavior of Cu/Fe-Al2O3, Cu/Fe-Al2O3-MoS2, and Cu/Fe-Al2O3-MoS2-h-BN hybrid composites are investigated against the EN 31 steel ball. The effects of various constituent reinforcing materials in the Cu-based composites on their friction and wear characteristics are studied at variable loads (2 to 8 N). The worn surfaces of the specimen and counter steel balls are examined by scanning electron microscope, atomic force microscope, subsurface deformation analysis, and x-ray diffraction, while wear debris particles are analyzed by SEM to understand the wear mechanism. The friction coefficient and wear rate are increased for Cu/Fe-Al2O3 composite with increasing load, and the wear mechanism changed from oxidative/delamination to third body abrasion. The coefficient of friction showed no significant changes with increasing of load (2 to 4 N) for Cu/Fe-Al2O3-MoS2 hybrid composite, whereas the wear rate is increased. Increasing load beyond 4 N decreased the wear rate, and it could be attributed to the formation of a compact layer. The coefficient of friction and wear rate of Cu/Fe-Al2O3-MoS2-h-BN hybrid composite increased with increasing of load up to 4 N. It was followed by the reduction of friction and wear rate with rising of the further load. The higher load formed a smeared layer for enhancement of tribological properties. © 2019 IOP Publishing Ltd.