Fabrication and Characterization of Silicon Carbide and Graphite Reinforced Aluminium Matrix Composite

Fabrication of Aluminium-based metal matrix composites has proved to be one of the most promising alternatives to the conventional alloying methodologies in recent times for manufacturing lightweight materials with high strength bearing capacities. Apart from possessing appreciable mechanical properties, these fabricated composites are also expected to withstand significant wear resistance for various applications in extreme conditions. Braking pads can be considered as one of such applications which demand the material to be extremely resistant to high abrasion even at elevated temperatures. Hence the use of composites on such occasions is not uncommon. Owing to the significant increment in strength and toughness from the addition of SiC and the elevation of wear resistance by virtue of self-lubricating nature of graphite, they have proved to be the top choice for reinforcements. The present study deals with the fabrication and characterization of SiC and graphite-reinforced Aluminium LM6 alloys for their implementation as the primary constituent material in braking systems. Hence, the tribological analysis, comprising of estimation of the coefficient of friction, specific wear rate and wear track analysis of the fabricated composite, can be considered as the primary findings of the present study. The results indicated the ability of graphite to impart significant wear resistance at elevated temperatures. Employing the well-known stir casting methodology for fabrication purposes can also be considered as one of the highlights of the current investigation. The accurate assessment of mechanical properties was obtained through hardness, tensile and compression tests. Further, optical microscopy, electron diffraction spectroscopy and XRD analysis are presented with an aim to bridge the gap between theoretical expectations and experimental results. All the results were observed to be in good agreement with each other indicating the influence of SiC and Graphite reinforcements in elevating the mechanical properties of the fabricated composite. © 2022, The Institution of Engineers (India).