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Composite materials are developed with the sole intention of augmenting the properties of metal/alloy through the addition of reinforcing materials. The composite of Al-6082 alloy with 5%, 10%, 15% and 20% percent by weight nano-SiC particulate reinforcement was successfully fabricated using the standard stir casting method. Using the rule of mixture, the physical properties such as the density, Poisson’s ratio, and the Young’s modulus were computed for the fabricated composites. The rule of mixture showed that the density and Young’s modulus was highest for composite with 20% nano-SiC reinforcement at 2.802 gms/cm3 and 136.2 MPa respectively. Whereas the Poisson’s ratio was maximum for composite with 5% nano-SiC reinforcement at 0.3225. For the strength evaluation, aappropriate specimens were prepared according to ASTM standards from the fabricated composites to test the hardness, tensile strength, compression strength, and impact strength. The hardness was tested using the Brinell’s hardness tester, which showed an increasing trend in the BHN, from 5% to 20%, at 84.34 to 93.39 N/mm2 respectively. The tensile tests showed an increasing tensile strength with a maximum measured at 327.94 MPa, for composite with 15% SiC. The tensile strength however reduced with further increase in nano-SiC reinforcement content at 20%. The compression tests showed a gradual increase in the compressive strength starting at 28.96 MPa for 5% nano-SiC reinforcement content, to 48.97 MPa for 20% nano-SiC reinforcement content. The impact tests conducted using the Charpy Test showed a gradual decrease in the impact strength starting at 6.2 Joules for 5% nano-SiC reinforcement content, to 4.8 Joules for 20% nano-SiC reinforcement content. This is due to the reducing toughness in the composites with a gradual increase in the nano-SiC reinforcement. The strength evaluation showed that for applications requiring maximum hardness and compression loads, the MMC of Al-6082 with 20% nano-SiC reinforcement would be best suited. It was also concluded that the applications with maximum tensile loading requirements, the MMC of Al-6082 with 15% nano-SiC reinforcement would be suitable. Furthermore, the impact strength evaluations has shown that the composite is highly unsuitable for applications with impact loading conditions. |
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