Effect of graphene reinforcement on the mechanical properties of Ti^sub 2^AlC ceramic fabricated by spark plasma sintering

Composite of Ti2AlC and 2 vol% Graphene nanoplatelets (GNP) was successfully fabricated by spark plasma sintering (SPS) technique to augment the fracture strength of Ti2AlC. Microscopic analysis revealed the reinforcement of GNP within the Ti2AlC ceramic matrix. As the consequence of positive reinforcement, there was a 335% improvement in the fracture energy of the GNP/Ti2AlC composite, 195% increase in the flexural stress and 41% increase in the flexural strain. From nano-scratch analysis at low load (7000 µN) and high temperature (300 °C), it was found that the GNP/Ti2AlC composites wear volume loss minimized by 75% as compared to pure Ti2AlC. Post microscopic analysis of the fractured surface gave insight into the improvement in fracture strength of the material by sheet sliding, crack deflection but mainly by the pull out mechanism of graphene from the Ti2AlC matrix. It was also found that GNP was sintered to Ti2AlC platelets thus improving the overall mechanical properties of the GNP/Ti2AlC composite.