材料科学与工程学报2012，Vol.30Issue(5)：659-665,7.
燃烧合成Si3N4和SiC复相材料的相稳定性热力学分析
Thermodynamic Analysis of Phases Stability for Combustion Synthesis Si3N4 and SiC Composite Raw Materials
摘要
Abstract
In order to enhance productivity and reduce cost,Si3N4 and SiC composite powder was synthesized by combustion after mechanical activation and chemical incensitive.Silicon powder and nitrogen gas were used as raw materials,carbon and silicon dioxide as diluent,and ammonium halide as chemical incentive agent.Thermodynamic analysis shows that silicon oxide and carbon as diluents to replace silicon nitride needs specific process conditions.Only when silica and carbon content are about 30 wt%,silicon nitride and silicon carbide composite powder can form.Assuming the carbon activity is 1(ac=1),the equilibrium temperature for the coexistence of Si3N4 and SiC in the combustion synthesis system is 1647K.At the same time,the complete nitrogenation of silicon powder needs high nitrogen partial pressure and low oxygen partial pressure,but not high temperature.When the necessary and appropriate process condition(9% Si3N4 and 15% mixture of starch and SiO2 content,more than 3MPa nitrogen pressure,5 hours milling) is met,the combustion synthesis product is free of silicon,but mainly composed of Si3N4,SiC and Si2N2O crystal phases,,which is an ideal composition as the raw materials of Si3N4-SiC dual phase ceramics and Si3N4 bonded SiC refractory.关键词
Si3N4/SiC/燃烧合成/相稳定性/热力学Key words
Si3N4/SiC/combustion synthesis/phases stability/thermodynamic analysis分类
化学化工引用本文复制引用
陈松林,袁林,冯中起,刘锡俊,曾鲁举,杨筠,李江涛..燃烧合成Si3N4和SiC复相材料的相稳定性热力学分析[J].材料科学与工程学报,2012,30(5):659-665,7.基金项目
国家自然科学基金资助项目 （）
“863”国家高技术研究发展计划资助项目 （）
