Synthesis of α-SiC(6H) using 6H polytype SiC diluent by the seeding technique

The feasibility of alpha-SiC(6H) polytype synthesizing from the SiO2 + 2Mg + C mixture by a traditional combustion synthesis process is demonstrated using an iterative method, called the seeding technique. Using this method the effect of an addition of commercial alpha-SiC(6H) powder on the SiC2 + 2Mg + C combustion synthesis system was investigated. The formation of a-SiC(6H) polytype in the reaction products has been confirmed by X-ray diffraction technique. The optimal conditions to obtain phase pure alpha-SiC(6H) having crystalline shape and a size about 0.5-1 mu m have been demonstrated through the seeding technique. (C) 2008 Elsevier B.V. All rights reserved.