Study of the nitridation process of TiSi2 powder

This paper reports on the nitriding process of TiSi2 micro/submicrometer-sized powders. TiSi2 powders were treated under nitrogen flow, at 1100 °C, during various durations. The composition and morphology of the nitride powders are characterized by X-ray diffraction and observed on cross-section, prepared using ion polishing system by scanning electron microscopy whereas the chemical composition is analyzed by energy dispersive X-ray spectroscopy. All these analyses revealed that under nitrogen flow, TiSi2 grains are first transformed into a core-shell structure composed of TiN, surrounded by Si. Long nitriding treatments result in the complete transformation of Si3N4. These results are discussed in terms of various diffusion limitation phenomena.