Study of the microstructures and mechanical properties of aluminium hybrid composites with SiC and Al2O3

Aluminium metal-matrix composites are widely produced with different ceramic compounds as reinforcements to enhance their properties and to suit various structural applications. The present work involves the fabrication of Al7075 composites with silicon carbide (SiC) and aluminum oxide (Al2O3) as reinforcements through stir casting. Four specimens were produced with different compositions comprising SiC (3, 5, 7 and 9 w/%) and Al2O3 2 w/% in all the combinations. Mechanical properties like ultimate tensile strength (UTS), yield strength (YS), percentage of elongation (% of elongation) and hardness (VHN) were examined, along with fractography studies. The microstructural characterization of the composites was also studied through micrographs obtained from the scanning electron microscope (SEM). The test results revealed that the increase in the w/% fractions of the reinforcement materials caused an increase in the tensile strength, yield strength and hardness of the aluminium composite, except for the % of elongation, which is reduced with the addition of ceramic particles.