Fabrication and Characterization of Aa2024 Composites

Abstract

The Aluminium alloy-based metal matrix composites (AMMCs) are fast emerging due to their favorable properties like light weight, low density, high specific strength, high hardness, high temperature and thermal shock resistance, superior wear and corrosive resistance and finally high strength as compared to ordinary alloys. Composites are fabricated using aluminium alloy (AA-2024) as base matrix and silicon carbide and Fly ash as reinforcements.

This aim and objective is to produce AMMCs through stir casting process and study of Microstructural characteristics and mechanical properties with aluminium matrix, reinforced with silicon carbide (SiC) and FlyAsh (FA). In this study, Aluminium (AA-2024) is reinforced with Silicon Carbide (SiC) particles with the addition of fly ash, which is limited to 5% per composite. The MMCs are fabricated using stir casting technique. Various specimens are developed undergoing different weight fractions of SiC and fly ash in AA-2024. Homogenization and heat treatment processes (aging and solution treatment) are performed on the specimen to obtain uniformity in the metal matrix. Microstructural analysis is done on the specimen and it was found that for different weight fractions of SiC and Fly ash in the matrix composite (5% Fly ash only, 5% Fly ash + 6% SiC, 5% Fly ash + 8% SiC), the phases are uniformly distributed. Successful incorporation of SiC and Fly ash in base AA2024 alloy is found by the micro structural examination in the Olympus microscope. Upon examination, it is observed that the fine grains in the matrix are Fly ash particles and the coarser grains are Silicon Carbide. And by conducting Brinell hardness tests and tensile tests it was fairly observed that the hardness was increased. It was observed that thereis increase in tensile strength but elongation of the hybrid metal matrix composites in comparison with unreinforced aluminum was decreased.