Tribo-Mechanical Behaviour of Ti-Based Particulate Reinforced As-Cast and Heat Treated A359 Composites

This study investigates the tribo-mechanical behaviour of as-cast and heat treated A359/ 6 wt.% Ti-based particulate reinforced homogeneous composites (TiB2, TiO2, and TiC) processed through modified stir casting technique. Metallographical observation on as-cast homogeneous composites revealed a uniform distribution of reinforcements throughout the cross-section. In heat treated composites, the tribo-mechanical properties were enhanced by the formation of spheroidized alpha eutectic Si. TiB(2)and TiO(2)exhibited superior interfacial bonding with Al-matrix, whereas TiC showed marginal wetting. Linear reciprocating wear experiments were performed on all as-cast and heat treated components by varying loads (15-55 N) and sliding distances (500-2500 m). Results revealed superior hardness (182.5 HV), tensile strength (271.6 MPa) and wear resistance for heat treated A359/TiB(2)composite than TiO(2)and TiC reinforced composites. The wear rate and coefficient of friction was observed to be dependent on the applied load and type of reinforcement particle in the composites. Worn surfaces of composites exhibited severe delamination wear mechanism.