Preparation of SiC/Si ₃N ₄ composites with rod-like microstructure by combustion synthesis

SiC/Si ₃N ₄ composites with rod-like microstructure were successfully prepared from a mixture of Dy ₂O ₃, amorphous carbon (carbon black) and Si powder in static N ₂ atmosphere using combustion synthesis (CS) in combination with a controlled pre-reaction mechanical activation treatment. The results showed that a large number of crystals with rod-like microstructure which were made of SiC and Si ₃N ₄ appeared in the product. The present work demonstrated that Dy ₂O ₃ is a good additive for the preparation of SiC/Si ₃N ₄ composites with rod-like microstructure, and the pressure of N ₂ is also an important factor.