부산대학교 도서관

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 ±7.0MPa)±2.82BHN) and hardness (120 ±7.0MPa)±2.82BHN) but lower % elongation than the other materials. The impact test of the materials was performed at various conditions (room temperature (RT), 0 °C, − 25 °C, − 50 °C and − 75 °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 °C, 175 °C, 250 °C and 325 °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.