Evaluation of Mechanical and Thermal Properties of Aluminium-7475 Reinforced with Graphite and Fly ash

Abstract

The aluminium is used for variety of reasons and they are known for their improved strength, stiffness, wear resistance which are useful in the marine, space, transport, automobile related industries. When aluminium reinforced with ceramic materials like fly ash, silicon carbide, tungsten carbide, boron carbide, fired bricks then a composite of better plastic forming capability, excellent heat and wear resistance will be formed. The objective of the experiment is to assess the thermal and mechanical properties of the Aluminium Metal Matrix Composites (AMMCs) when reinforced with ceramics. Aluminium (Al-7475) based metal matrix composites reinforced with varying weight percentage of Graphite(Gr) (3%, 6%, 9% and 12%) and fly ash being constant (10wt%) by the stir casting process. The composites tensile strength and hardness improved with the amount of graphite content improved in weight percentage up to 9% then decreased. While the composite’s Thermal Conductivity(TC) and Coefficient of Thermal Expansion(CTE) varying temperature range from 50°Cto 300°C reduces with increase in weight percentage of the graphite content.