摘要
采用自蔓燃高温合成方法(SHS)合成氮化硅粉体,借助于XRD、SEM等检测方法,分析了自蔓燃高温合成氮化硅过程中氮气、温度、稀释剂与孔隙率等工艺参数对合成产物的影响。结果表明:只要最高燃烧温度不高于相应氮气压力下Si3N4的热分解温度,就可以用SHS方法合成Si3N4;氮气压力下硅粉的自蔓燃合成反应,必须要引入Si3N4稀释剂来控制反应温度,获得高α相Si3N4含量的粉体。压坯气孔率控制在30%～70%,否则反应不能进行。SHS法可以制备纯度很高的氮化硅粉体。
Si3N4 powder was prepared by the self-propagating high-tem- perature synthesis （SHS） and X-ray diffraction and SEM were used to examine the Si3N4 powder. The following parameters were discussed： nitrogen purity and pressure, combustion temperature, diluents content and the porosity and so on. The experiment results showed that the SHS reaction between Si powder and nitrogen would proceed at low nitrogen pressure as long as combustion temperature no higher than the decomposition temperature of Si3N4. Under response nitrogen pressure Si3N4 would be obtained from silicon powder as starting raw materials in order to control reaction temperature and obtain high the content of α Si3N4 powder, the porosity of body was controlled at 30%- 70% ,otherwise, it was not able to react. The results indicate that the SHS method can prepare Si3N4 powders with high purity.
出处
《中国粉体技术》
CAS
2008年第4期1-3,共3页
China Powder Science and Technology
基金
国家科技攻关计划项目
编号:2003DFBA0010。
关键词
自蔓燃高温合成
氮化硅
工艺参数
self-propagating high-temperature synthesis
silicon nitride
processing parameter
