Effect of load on the tribological behavior of self-lubricating hybrid aluminum composite under dry sliding conditions

Abstract

Self-lubricating composites are the new development of next generation. Hence the objective of this study is to determine how Aluminum Oxide (Al2O3) and Graphene Nano Platelets (GNP) nanomaterial reinforcements could be used to enhance the tribological properties of Eutectic Aluminum-Silicon matrix material. Friction and wear studies of self-lubricating novel Aluminum-Silicon/Aluminum Oxide/ Graphene Nano Platelets (Al-Si/Al2O3/GNP) hybrid composite with varying amount of Graphene Nano Platelets (GNP); synthesized using Spark Plasma Sintering (SPS) has been studied in this research paper. The tribo-testing was done on the ball-on-disc configuration under dry sliding conditions. Effect of the solid self-lubricating composite was studied under room temperature at high load varying from 50N-300N with chrome plated chrome steel ball as counter-body and other parameters i.e. frequency, stroke, sliding distance remained constant throughout the experimentation. The results of the tribo tests indicates that the novel hybrid composite fabricated using both reinforcement’s nanomaterial exhibit excellent antifriction as well as antiwear. Results showed that best tribological properties were achieved for composite sample having 4 wt% of GNP. Reduction in friction and wear of the hybrid composite was reported in the range 4.04%–12.47% and 61.87%–82.84% respectively, compared to the base matrix material (Eutectic Al-Si alloy). It was observed that the seizure phenomenon which occurs with monolithic Aluminum-Silicon (Al-Si) alloy did not occur with hybrid composite. The surface morphology and wear surface analysis were done by using Optical Microscopy , Scanning Electron Microscopy , Electron Dispersion Spectroscopy and 3D Surface Profilometer. The results of this research highlights the novel self-lubricating hybrid composite which can be used in manufacturing of various mechanical components applications.