Wear and Hardness Studies of Graphene Decorated with Graphene Quantum Dots (G-D-GQD) Embedded Epoxy Nano Composites

Abstract

The paper discusses about the wear and micro hardness behavior of Graphene Decorated with Graphene Quantum Dots (G-D-GQD) reinforced epoxy composites. The samples were prepared by open mold casting method by adding 0.25–1 wt. % (in an interval of 0.25%) of GDGQD and evaluated on a reciprocating wear tester configuration for wear and coefficient of friction properties. The micro-hardness testing of the G-D-GQD particles embedded epoxy composites has been performed and the hardness value results were compared with neat epoxy to find the improvement in hardness. Significant improvements in the hardness and wear resistance of the epoxy nanocomposites was obtained by the embedding of G-DGQD fillers, which is due to the efficient bonding of GDGQD filler with the epoxy matrix. Scanning Electron Microscope (SEM) images of the worn composites were analysed to get an insight into the morphology of the surfaces. Furthermore, the coefficient of friction of the composites got increased with the wt. % of fillers in the base material, but due to the superior bond strength and lesser agglomeration of the particles, the Vicker's hardness improved and the wear loss reduced. Hence the surface area coverage of G-D-GQDs got a significant role in the reduced wear loss and thereby coming to a threshold value. The study concludes by suggesting that 0.25 wt. % GDGQD/epoxy composites shown a least wear rate and increased hardness of 0.023% and 26%, respectively thereby suggesting application involving reduced wear rates.