Low Cost In-Situ Formation of AIN - B- SiC

AIN-a-SiC composite powders have been prepared by in-situ high temperature reaction process. By appropriate mixing of Charred Rice Husk (CRH) and aluminium powder, samples containing 30-70% A1N (balance SiC) have been produced. Nitridation has been done by high purity N, gas at temperatures ranging from 1400-17000C.Amorphous SiO, and carbon present in CRH have been utilized for the formation of [i-SiC.
At about 1550°C the reaction products are only [3-SiC and AIN, whereas,below 1550°C other phases, like a-A1,03, Al, Si are the reaction products. It has also been observed that above 1600°C SiC starts going into the solid solution of A1N. The final products have been identified and characterized by XRD, SEM and EDX analysis.