Kinetics of Nitridation of Si Powder Compacts

Abstract

The kinetics of the reaction of Si powder compacts and N 2 to form Si 3 N 4 were investigated thermogravimetrically from 1300° to 1450°C. The results indicate that trace amounts of O 2 inhibit the rate of nitridation by forming a thin protective layer of SiO 2 , whereas Fe impurities catalytically accelerate the rate of reaction by liquid‐phase formation. Complicating factors that account for difficulties in interpreting the reaction kinetics and for the poor agreement among previous investigations are discussed.