Synthesis and characterization of in-situ reinforced Fe-TiC steel FGMs

This paper presents a novel technique to synthesize TiC-reinforced iron base (Fe-TiC) functionally graded materials (FGM) using SHS reaction followed by centrifugal casting. The in-situ reinforced Fe-TiC steel composites were prepared by aluminothermic SHS reactions using metal oxides and elemental powders. Ferritic as well as austenitic matrix Fe-TiC composites were obtained by judicious thermite charge composition. FGM microstructure was characterized in terms of TiC area fraction, particle size, and chemical analysis using optical and analytical electron microscopy. The results reveal a gradient of TiC particles across the thickness in the inner face and a particle-free region in the outer surface. Hardness profiles have shown an increasing trend from outer surface to TiC-rich inner surface. Wear studies indicated better wear performance of TiC-rich inner face as compared to particle-free outer surface of ferritic or austenitic steel matrices.