Effect of fine silicon powders addition on improving nitridation of coarse silicon powders

Abstract The fabrication of large silicon nitride particles via direct nitride is time‐consuming. In this work, the effect of adding fine silicon powders (5 μm) on improving the nitridation of coarse silicon powders (50, 150 μm) at 1450°C in a thermogravimetric analyzer was investigated. The addition of fine silicon particles prevents the coalescence of the melted coarse silicon particles, due to them converting to silicon nitride particles more quickly. Less time is required to complete the nitridation of coarse silicon as the amount of fine silicon increases. The nitridation of coarse silicon (150 μm) is completed in less than 23 min at 1450°C with adding 50% fine silicon. The nitridation products consist of particles similar in size to the raw silicon particles.