The effect of Mo 2 C additions to a NbC-12vol%Ni-0.5vol%WC material on sintering at 1450°C and on the resulting microstructure was investigated by replacing different amounts of NbC with Mo 2 C (0%, 3%, 6% or 9% in volume) and by performing interrupted tests at key temperatures (1080°C, 1180°C and 1320°C). Chemical reactions and phase transformations were followed by Thermogravimetric Analysis (TGA) and sintering behavior by dilatometry. The microstructure was studied by Scanning and Transmission Electron Microscopy (SEM and TEM), Energy Dispersive Spectrometry (EDS) and X-ray diffraction (XRD). It is observed that Mo 2 C and WC particles, present at the onset of solid state sintering, delay the shrinkage of the material. An increase of hardness with Mo 2 C addition is measured, mainly due to grain refinement.

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