Simultaneous nitriding of silicon and aluminum

During the high-temperature nitriding of silicon-aluminum mixtures in nitrogen and ammonia the mixture components undergo nitriding separately, first aluminum and then silicon. Aluminum inhibits the nitriding of silicon, shifting the process toward higher temperatures. The inhibition is apparently due to a reaction between the silicon nitride and aluminum, with the formation of aluminum nitride films on the silicon particles. The nitriding of silicon and aluminum in nitrogen results in the formation of a limited solid solution of aluminum in a silicon nitride based onβ-Si3N4.