Abstract
The present study was conducted to examine the physical, metallurgical, mechanical, and tribological behaviors of A356 alloy reinforced with fly ash (5, 10 wt%), and SiCp (2.5 wt%) hybrid composites. Three hybrid composites were synthesized and consolidated through a stir cum squeeze cast technique followed by solution treatment and aging. X-ray diffraction and microstructural evaluations were performed using an optical microscopy and a scanning electron microscopy. The microstructural results revealed pore-free, homogeneous dispersions and effective bonding of reinforcements in the matrix. The experimental bulk density of the A356-10wt% fly ash-2.5 wt% SiC hybrid composite exhibited lower value compared with other samples indicating lighter weight. The same sample produced Brinell hardness number of 90.35 +/- 3.80 HB and ultimate strength of 329 MPa which was 1.28 times and 1.14 times higher than matrix respectively. The dry sliding wear test results showed that the wear rate and coefficient of friction started to increase with increasing applied load and sliding speed. The 10 wt% fly ash sample produced lower wear rate 1.42 x 10(-3) mg/m at a load 10 N and sliding distance of 1000 m. Finally, the surface worn-out mechanisms were studied using SEM. The developed 10 wt% fly ash-based hybrid composite exhibited improved performances recommending to use in automotive and various structural parts.