Influence of carbon content on the sinterability of an FeCr matrix cermet reinforced with TiCN

The influence of carbon content on an iron-chromium cermet composite reinforced with Ti(C,N) (50 vol.%) has been studied. A thermodynamic simulation was performed using the ThermoCalc software to calculate the phase diagram of the composite. The results were validated by a thermal study performed using differential thermal analysis (DTA), and cermet samples with C percentages between 0 and 1 wt.% added to the steel matrix were prepared using a conventional powder metallurgy process. The sintered samples were characterised by measurements of density and hardness, microstructural analysis using scanning electron microscopy (SEM), microanalyses using energy dispersive X ray spectroscopy (EDX) and X-ray diffraction (XRD). The results obtained show a significant influence of the C percentage on the solidus temperature, which influences sintering behaviour, leading to changes in the Ti(C,N) particles' shape and composition, due to changes in the stoichiometry of the Ti(C,N). This influence is reflected in the cermet microstructure and hardness. The results are discussed with reference to the DTA and thermodynamic studies.The authors would like to acknowledge the financial support of the Spanish Ministry of Science and Innovation through R&D Project MAT2009-14448-C02 and the Regional Government of Madrid through the programme ESTRUMAT-CM (Ref. S2009/MAT-1585).Publicad