Abstract
TiAl composites reinforced with Ni/TiCN were fabricated via spark plasma sintering. The microstructure of the unreinforced TiAl (T) exhibited a dense gamma-TiAl/alpha 2-Ti3Al lamellar structure, while TNiTiCN composites exhibit in-situ formation of Ti2Ni and Ti3AlC2 MAX-phase. Microhardness increased systematically with increasing TiCN addition, reaching a maximum of 434 HV1.0 in TNi6TiCN composite, though with increased scatter due to particle agglomeration. Tribological results revealed that the TNi3TiCN composite exhibits the lowest coefficient of friction (0.186 +/- 0.015) and wear rate (1.268 +/- 0.35 & times; 10-4 mm3/Nm). However, higher TiCN content induced clustering, leading to localised spallation and degraded wear resistance despite higher hardness.