Synthesis of Si3N4

In the present paper results obtained during synthesis of Silicon Nitride by Self-propagating High-temperature Synthesis (SHS) are shown. Self-propagating High-temperature Synthesis is based on the high enthalpy of certain reactions able to be self-sustained. One of the most important advantages of the method is its very low energy consumption. The synthesis is carried out with a mixture of silicon powder with some additions of diluents and other synthesis aids (ammonium salts). The influence of the mixture composition on reaction parameters and characteristics of the obtained products has been studied. The use of new synthesis aids has been also studied in order to decrease the environmental impact of the process. Microstructural study, XRD and reaction parameters are shown. Finally a mechanism of Silicon Nitride synthesis is proposed.