Sample Controlled Reaction Temperature (SCRT): Controlling the Phase Composition of Silicon Nitride Obtained by Carbothermal Reduction

Carbothermal reduction of silica is one of the most common methods of producing Si3N4 powders. The experimental conditions have an important influence on the structure of the final product, especially the balance of α- to β- Si3N4. The Sample Controlled Reaction Temperature method describes here has permitted to conclude that the phase composition of the silicon nitride is governed by the partial pressure of CO in the close vicinity of the sample. Moreover, the control of this parameter has an important influence on particle size and morphology of the final product.