Production and Mechanical Testing of Aluminium Alloy Based Hybrid Metal Matrix Composite

The present work aims for uniformly dispersing Aluminium Oxide (Al₂O₃) and Graphite (Gr) particulates in an Aluminium Alloy Matrix to produce a hybrid composite and then to carry out the investigation and analysis of mechanical properties of developed composite. The particle size of Al₂O₃ and Gr were less than 45 microns. The stir casting technique is utilized to produce the hybrid composite having 2% Al₂O₃ with 0.5%, 1% Gr and 4% Al₂O₃ with 0.5%, 1% Gr. The composites were studied for density changes due to reinforcements, hardness, tensile strength and wear behaviour in Non-Heat Treated (NHT) conditions. The tests were done at the laboratory conditions as per ASTM guidelines. The Pin-On-Disc machine is used to test the sliding wear behaviour under dry conditions. The measured density is found to be decreasing as the reinforcement quantity is increased. The as cast Al alloy was found to be having highest hardness and the composites with increasing Gr exhibited lower hardness. The composite tensile strength is observed to be decreased in comparison to base alloy due to the presence of Gr but composite having highest quantity of Gr showed superior wear resistance which is mainly because the Gr particulates provide an inherent lubricating properties to composite. The composites developed in the present work can be used in the automobile and aerospace parts that are light in weight and require self-lubricating properties to enhance the wear resistance.