Mechanical Properties Response of Heat Treated Recycled Aluminium Alloy Reinforced with Gold Nanoparticle (AuNps) Extracted from Aloe Vera Leaf

Abstract

Aluminium and its alloys are becoming more widely used in engineering due to a growing need for lightweight metals. However, owing to boundary segregation and coarse dendritic grains, typical cast aluminium alloys have low hardness and strength, limiting their use in large-scale and complex-shaped applications. Many studies have shown that reinforcing aluminium alloy with nanoparticles synthesized by various chemical and physical ways improves these shortcomings, but these approaches are both expensive and potentially dangerous. Recycling aluminium scrap is also necessary to save energy and money. Therefore, this research aimed at production of high tensile strength and hardness from scrapped aluminium reinforced with synthetic nano particle and subjected to heat treatment. The elemental composition of aluminium alloy cast from scrap was analyzed using a Light Emission Polyvac Spectrometer, and gold nanoparticles were synthesized from aloe vera leaves. In creating a Metal Matrix Nano Composite, Al alloy was reinforced with gold nanoparticles at various percentages. At 450 °C, the reinforced Metal Matrix Nano Composite was hardened. The composites' hardness, tensile strength, and microstructural analyses were determined. The composites' grain structure demonstrated a uniform distribution of reinforcing phase of Al 6063 Alloy. The microhardness and tensile strength of the composites are influenced by the % weight proportion of AuNps and the heat treatment. After 3 percent and 6 percent weight of AuNps reinforcement were used, the microhardness/tensile strength of the reinforced sample rose by 22.4 Hv/58MPa and 24.7 Hv/80MPa, respectively, but when the composites were hardened, it climbed to 41 Hv/109 MPa and 45.5 Hv/125 MPa. After 3 percent and 6 percent weight of AuNps reinforcement were used, the microhardness/tensile strength of the reinforced sample rose by 22.4 Hv/58MPa and 24.7 Hv/80MPa, respectively, but when the composites were hardened, it climbed to 41 Hv/109 MPa and 45.5 Hv/125 MPa.