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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]

A wet ball milling route was used to synthesise SiC-graphene core-shell nanoparticles in situ from graphite and SiC nanoparticles. Graphite flakes were gradually exfoliated into fresh graphene nanosheets (GNSs) without significant defects, which is attributed to mechanical shearing and moderate impaction forces between graphite flakes, milling balls and SiC nanoparticles during the wet milling. The non-destructive exfoliation is characterised by Raman, Fourier transform infrared and X-Ray photoelectron spectroscopies. The freshly produced GNSs are energetically unstable and thin enough to be flexible and this drives the in situ attaching and scrolling of GNSs on the SiC nanoparticles. The SiC nanoparticles and GNSs are well dispersed in the wet medium and the SiC nanoparticles are individually wrapped. It has been estimated that > 50% of the produced GNSs are wrapped around the SiC nanoparticles and these GNSs are generally ≤ 6 layers. [ABSTRACT FROM AUTHOR]