Microstructures and properties of FeAl-Fe₃AlC_0.5 composites prepared by SHS casting

FeAl composites with 21, 37 and 50 wt pct Fe₃AlC_0.5 were fabricated by a self-propagating high temperature synthesis (SHS) casting. Phases and microstructures were analyzed by X-ray diffraction (XRD) and scanning electron microscopy (SEM). Microhardness and bending strength of the composites were measured. The composites with 21 and 50 wt pct Fe₃AlC_0.5 mainly consisted of FeAl and Fe₃AlC_0.5 phases, whereas the composite with 37 wt pct Fe₃AlC_0.5 was composed of FeAl, Fe₃AlC_0.5 and graphite phases. The bonding of the reinforcement and the matrix was good. Hardness and bending strength of the composite with 37 wt pct Fe₃AlC_0.5 was lower than those of the 21 and 50 wt pct composites owing to the presence of the soft graphite phase.