Sintering and Mechanical Properties of (SiC + TiC_x)_p/Fe Composites Synthesized from Ti₃AlC₂, SiC, and Fe Powders

Ceramic-particle-reinforced iron matrix composites (CPR-IMCs) have been used in many fields due to their excellent performance. In this study, using the fast resistance-sintering technology developed by our team, iron matrix composites (IMCs) reinforced by both SiC and TiC_x particles were fabricated via the addition of SiC and Ti₃AlC₂ particles, and the resulting relative densities of the sintering products were up to 98%. The XRD and EDS analyses confirmed the in situ formation of the TiC_x from the decomposition of Ti₃AlC₂ during sintering. A significant hybrid reinforcing effect was discovered in the (SiC + TiC_x)_p/Fe composites, where the experimental strength and hardness of the (SiC + TiC_x)_p/Fe composites were higher than the composites of monolithic SiC_p/Fe and (TiC_x)_p/Fe. While, under the condition of constant particle content, the elongation of the samples reinforced using TiC_x was the best, those reinforced by SiC was the lowest, and those reinforced by (SiC + TiC_x) fell in between, which means the plastic response of (SiC + TiC_x)_p/Fe composites obeyed the rule of mixture. The successful preparation of IMCs based on the hybrid reinforcement mechanism provides an idea for the optimization of IMCs.