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Abstract Graphene encapsulated SiC nanoparticles were incorporated into aluminium matrix composite (AMC) and its tribological behaviour was investigated under dry sliding wear. SEM, 3D-laser, TEM and Raman microscopies were employed to characterise the composite. It was found that the wear rate and coefficient of friction of the composite were 98.0% and 35.9% lower than that of the reference sample reinforced with solely SiC nanoparticles respectively. The improved tribological properties are probably attributed to the uniform distribution of graphene nanosheets in the bulk composite which smeared on the wear scar and formed graphene-rich micro tribofilms during the sliding wear. [ABSTRACT FROM AUTHOR]

Abstract SiC-graphene nanosheets (GNSs) core-shell nanoparticles were incorporated into alumina matrix composites. The composites showed refined grain sizes, increased toughness and hardness. Ball-on-disk wear tests were conducted and the results demonstrated that the coefficient of friction was reduced by 29.4%, and the wear rate was reduced by 90.1% for the composite containing 5 vol % SiC and 1 vol % GNSs at 90 N in comparison to monolithic alumina. These results are superior to Al 2 O 3 -graphene composites documented in the literature. The microstructure and topography of the wear scars were examined to understand the wear behaviour. GNSs-rich tribofilms were observed on the wear scar. The contributing mechanism of the self-lubricating and wear-resistance performance was explored. Highlights • The composites showed excellent wear-resistant and self-lubricating performance. • The reduction effect of the nanofiller on friction tends to be more significant under higher loads. • The enhancement is attributed to the improved microstructure, mechanical properties and GNSs-rich tribofilms. [ABSTRACT FROM AUTHOR]