Wear resistant properties of multi-walled carbon nanotubes reinforced Al2O3 nanocomposites

Various amounts of well-dispersed multi-walled carbon nanotubes (MWCNTs) were used to reinforce an Al2O3 via a hot-press consolidation. Ball-on-disk wear tests were performed under different loading conditions of 14 N, 25 N and 35 N, to evaluate the wear and tribological properties of the Al2O3–MWCNT nanocomposites. In comparison with the monolithic Al2O3, the addition of MWCNTs decreased the coefficient of friction in Al2O3–MWCNT nanocomposites and a promising 80% reduction in coefficient of friction was recorded for nanocomposite containing 10 wt% MWCNTs, under a sliding load of 14 N. Abrasive sliding wear mechanism was observed in all samples. The results show that additions of MWCNTs can upgrade the monolithic Al2O3 and convert it into a wear resistance material. The MWCNTs played dual roles in improving the tribological performance of the nanocomposites, indirectly by influencing the microstructure and mechanical properties of nanocomposites and directly by acting as a lubricating medium.