Experimental investigation and thermodynamic analysis of TiC–Fe cermets with Mo additions

Abstract

In this study, the effects of Mo additions on the microstructure, hardness and bending strength of TiC–Fe cermets manufactured by spark plasma sintering were investigated by scanning electron microscopy, X-ray diffraction and mechanical properties tests. Thermodynamic calculations were utilized to analyze the evolution of the microstructure. The results show that the conventional core/rim structure was not formed during the solid-phase sintering of TiC–Fe cermets. The heat-treatment process and reasonable Mo addition can effectively enhance the overall performance of the alloys. With the addition of minor Mo, the hardness of the sintered cermets improved significantly, which was attributed to the solid solution strengthening mechanism of Mo in Fe binder. However, excessive Mo exceeded the solubility range of Fe binder and precipitated in the form of M 6C and Mo2C phases, which damaged the bending strength of the heat-treated cermets.