Microstructure, Mechanical and Tribological Properties of Al7075/SiC/Graphite Hybrid Metal Matrix Composites

Particulate reinforced aluminium hybrid composites are becoming more popular in automobile, aero and industrial applications. The current work attempts to produce self-lubricating particulates into Al7075–5wt% SiC–xwt% graphite ( x = 0, 5, and 10) hybrid-composite via the powder metallurgy method. The hybrid composites' density, hardness, microstructural, and tribological properties were studied. The Taguchi experimental design was used to investigate the ideal testing settings utilising an orthogonal array, the signal-to-noise ratio, and analysis of variance. It was observed that reinforcement particles are homogeneously dispersed in the matrix alloy as fine dendrites in aluminium from SEM examination. According to the results. The wear loss increases as the sliding distance and load increase but decreases as the graphite weight percentage increases. Therefore, a confirmation test was also performed with the optimized parameter combinations to validate the Taguchi findings, reducing wear loss by around 45.11% and the friction coefficient by 68.50%. The wear-mechanism has described creating both an adhesive layer and an interfacial layer. The wear mechanisms were explained by examining through SEM and Edax. The wear resistance and friction coefficient of aluminium hybrid composites improved significantly by incorporating a solid lubricant and hard ceramic reinforcing particulate in the matrix alloy.