Microstructure and Wear Study of Al 7075-T6/Eggshell/SiC/Al₂O₃ Hybrid Composites

In present experimental investigation, hybrid aluminium metal matrix composites were fabricated using stir casting technique by infusing eggshell particles (0.5, 1 wt%), SiC particles (1, 1.5 wt%) and Al₂O₃ particles (1.5, 2.5 wt%) into Al 7075-T6 metal matrix. The developed composites were further characterized for microstructures using FESEM, X-ray diffractometry and EDS techniques. Tribological behaviour investigations were carried out using a pin-on-disk tribometer for comparative study between as-cast Al 7075-T6 alloy and Al-7075-T6/Eggshell/SiC/Al₂O₃ composites. During dry sliding wear test at room temperature, there was a decrease of 33% in wear rate, 20% in coefficient of friction and 20% in frictional force of composites, whereas in presence of lubricant, the developed composites exhibited maximum reduction of 85% in wear rate, 46% in coefficient of friction and 46% in frictional force as compared to their unreinforced counterparts. Due to augmented tribological properties, fabricated hybrid composites can reasonably be used for lightweight wear-resistant applications.