EFFECT OFK_2O ON SYNTHESIS OFAL_4SiC_4/Al_4O_4C COMPOSITES

摘要

Al_4SiC_4 and Al_4O_4C are two promising materials for their excellent physical and chemical performances. When they are synthesized by using some raw mineral materials, the impurities of the starting materials inevitably play some roles. In this paper, flint clay, Al and C powders by adding different mass of K_2O as raw materials had obtained 20~50μm and hexagonal plate-like grains of Al_4SiC_4 at lower heating temperature and shorter holding time than that without adding K_2O. The K_2O mass of the products decreases with increasing heating temperature or additive amount of K_2O at one temperature. The role of K~+ is reacting with Al_4SiC_4 to form the finite substitution solid solution.