Influence of ceramic reinforcements on mechanical properties and high-temperature sliding wear behaviour of heat-treated Al6082-SiC-TiO2 composites developed by stir-casting process

This study investigated and compared the mechanical properties and high-temperature sliding wear response of different combinations of heat-treated aluminium metal matrix composites (Al6082-SiC-TiO2 composites) developed by stir-casting techniques. The study considers four types of materials: Al6082 alloy, 3% SiC reinforced with Al6082 alloy, 3% TiO2 reinforced with Al6082 and 1.5% SiC + 1.5% TiO2 reinforced with Al6082 (hybrid composite). After the successful preparation of materials, T-6 heat treatment was done, which improves the various properties of materials. The microstructural, mechanical properties and wear behaviour of the heat-treated materials were analysed to investigate their physical strength. The results showed that the hybrid composite had higher ultimate tensile strength (314 +/- 7.0 MPa) and hardness (120 +/- 2.82 BHN) but lower % elongation than the other materials. The impact test of the materials was performed at various conditions (room temperature (RT), 0 degrees C, - 25 degrees C, - 50 degrees C and - 75 degrees C). The hybrid composite exhibited a maximum impact energy of 6.35 +/- 0.32 J at RT compared to other developed materials. However, the impact energy decreased as temperatures dropped because ductility decreased at lower temperatures. The high-temperature sliding wear test was performed at different environmental conditions (RT, 100 degrees C, 175 degrees C, 250 degrees C and 325 degrees C) to recognise the tribological behaviour of materials. The study concluded that the hybrid composite showed a higher wear resistance than the material samples at other conditions, irrespective of the temperatures. The wear surfaces were analysed to determine the material removal mechanism.