Thermodynamical characteristics of partial reactions related to preparation of sialon powder from kaolin

Abstract

Sialon ceramic materials and its main three preparation methods have been outlined, among which preparing sialon powder from Kaolin through the carbothermal reduction and nitridation process is an economical, simple and practical synthesis process. However, the reaction system is complex due to the fact that there exist a lot of influencing factors and several reactions are taking place simutaneously. Partial reactions related to the chemical reaction system of the carbothermal and nitridation process, sialon powder prepared from the purified Kaolin, are analyzed thermodynamically, the systhesis temperature of sialon powder is 1400°C. The theoretical bases used to find the rational process of production are provided. The results prove to be practical.

Keywords

sialon powder / Kaolin / carbothermal reduction and nitridation process / thermodynamics / synthesis temperature