Development of Controller-Based Interchangeable Axis Centrifugal Casting Machine and Characterization of Aluminum-Silicon Carbide (Al-SiC) Functional Graded Composite

Centrifugal casting is one of the prominent and simple methods to produce functionally graded composites (FGC). Functionally graded composites are a class of materials which possess continuously varying properties along the radial direction. Functionally graded composites have a wide variety of applications in different fields of engineering. The processing method of functionally graded composite plays a vital role in defining its properties. Centrifugal casts can be produced in vertical (for short annular casts of larger diameters) and horizontal (for long annular casts of smaller diameters) axis machines. Two different machines are being used to cast FGCs based on the application. This work is about the development of controller based centrifugal casting machine, which can be used both in vertical and horizontal orientations to produce annular casts. The characterisation of Silicon Carbide reinforced aluminium matrix functionally graded composite produced from the developed machine is also carried out. The results depict that the hollow cylindrical cast produced from the machine possesses varying characteristics along the inner and outer regions of the cast. The hardness and the wear characteristics of the outer region are found to be better than those of the inner region of the FGCs. The outer region of the FGC sample (95% Al-5% SiC) exhibited a higher average hardness of 35.68 BHN, compared to 32.2 BHN in the inner region with the same composition. This indicates improved surface hardness in the outer layer due to structural gradient effects. At 40 N load, the inner sample exhibited a maximum wear rate of approximately 0.00018 mg/m, while the outer sample showed a lower rate of about 0.000094 mg/m. Across all loads (10-40 N), the inner region consistently recorded higher wear rates, confirming enhanced wear resistance in the outer FGC layer.