Oxidation of Ca-alpha-SiAlON Powders Prepared by Combustion Synthesis

The oxidation of Ca--SiAlON synthesized by the combustion synthesis (CS) method with different additives was investigated in air atmosphere using thermogravimetric (TG) analysis in a temperature range from 1453 K to 1653 K. The experimental results indicated that oxidation was controlled by mixed chemical and diffusion steps. The oxidation products by XRD analysis were composed of SiO2 and CaAl2Si2O8 at low oxidation temperature, whereas the SiO2-Al2O3-CaO ternary glassy phase was formed at elevated temperature. The deviation of oxidation resistance from each sample may be due to the morphological difference brought about by different additive additions. This study reveals the effects of additives on the oxidation resistance of synthesized Ca--SiAlON powders.National High Technology Research and Development Program of China (863 Program) [2012AA06A114]; Key Projects in the National Science & Technology Pillar Program [2011BAB03B02, 2013BAC14B07]; Common Development Fund of Beijing; National Natural Science Foundation of China [51472007, 51272005, 51522401]SCI(E)EIARTICLEleesanqiang@yahoo.com; pkulzm@163.com; wangeh1990@163.com; wangzhanjun1990@163.com; yinxw@nwpu.edu.cn; zuotaizhang@pku.edu.cn117549-7562