Processing and characterization of fly ash particle reinforced A356 Al composites

A356 Al-fly ash particle composites were fabricated using stir-cast technique. Bulk hardness and matrix microhardness of A356 AI-fly ash composites are higher compared to those of the unreinforced alloy. In the as extruded condition, 0.2% proof stress of the composites is higher compared to that of unreinforced alloy. Addition of fly ash leads to increase in hardness, elastic modulus and 0.2% proof stress. Composites reinforced with 12-volume % fly ash exhibits lower UTS compared to that of unreinforced alloy. Composites reinforced with narrow size range fly ash particles showed better mechanical properties compared to composites with wide size range particles. Damping behaviour of unreinforced alloy and their composites have been studied using dynamic mechanical thermal analyzer (DMTA). A356 Al-fly ash MMCs were found to exhibit improved damping capacity when compared to unreinforced alloy both at ambient and elevated temperatures.