Influence of thermal ageing on the microstructural and mechanical characteristics of banana stem particles reinforced aluminium-alloy matrix composites

Abstract

The influence of thermal ageing on the microstructural and mechanical characteristics of banana stem particles (BSp) reinforced aluminium-alloy matrix composites was investigated. Sand casting was used to produce the composites, comprising aluminium alloy matrix reinforced with BSp of varying weight ratio of 0 wt. %, 1 wt. %, 3 wt. %, 4 wt. %, 5 wt. % and 6 wt. % were thoroughly mixed. Test samples for mechanical characterisation were prepared from the sand cast (6 mm diameter by 125 mm rods for tensile test). Thermal ageing was done for 2 hours (hrs) at 350 ⁰C. The composites were evaluated for tensile, modulus of elasticity, hardness, and microstructural characteristics. The thermally aged samples demonstrated greater tensile strength and toughness as the concentration of BSp increased up to 5 wt. % in the composite in comparison with the as-cast samples. The greatest characteristics were demonstrated at 5 wt. % BSp concentration. Lower hardness was demonstrated by the as-cast samples in comparison with the aged-hardened samples. There was 5 wt. % BSp concentration in the alloy enhanced thermal ageing. These indicate that greater mechanical characteristics of the composites can be obtained by thermal ageing.