SiC加热元件在N_2气氛下使用损毁机理研究  

Damnification Mechanism of SiC Heating Elements Used in N_2 Atmosphere

作　　者：刘新红[1] 牛智旺 周超杰[1] 王大军 方岩震 刘锴 

机构地区：[1]郑州大学高温材料研究所,河南郑州450052 [2]河南省伯马股份有限公司,河南新乡453002

出　　处：《郑州大学学报（工学版）》2014年第3期18-21,26,共5页Journal of Zhengzhou University（Engineering Science）

基　　金：河南省科技创新杰出青年基金资助项目(124100510019);河南省重点科技攻关计划项目(112102210095);河南省科学技术研究重点项目科技攻关计划项目(14A430030)

摘　　要：用XRD和SEM对在N2气氛使用后SiC加热元件的物相组成和显微结构进行了分析,并对损毁机理进行了探讨,结果表明:未变质部分的气孔较多,腐蚀性气体易通过气孔与SiC反应造成损毁,并存在Si、K2O和FeSi杂质相,此杂质相也可加速损毁;由于在N2气氛中氧分压较低,不能形成保护性玻璃膜,N2中的少量O2易与SiC加热元件反应使其氧化导致结构疏松,加剧氧化损毁;炉内烧制的含Al、Si和C的耐火材料中挥发出的Al(g)、Al2O(g)和CO(g)等与SiC加热元件反应,生成β-SiC、SiO2和Al2O3,致使SiC加热元件变质损毁.Phase composition and microstructure of SiC heating elements used in N2 atmosphere have been analyzed by XRD and SEM, and the damnification mechanism of SiC heating elements is discussed. The results show： there are many pores in unchanged part which provide channels for the corrosive gas leading to damnification, and the impurities Si, K2O and FeSi would accelerate damnifieation during use; a protective film in the surface of SiC cannot form in N2 atmosphere due to low pressure of O2 , and the trace O2 in N2 atmosphere reacts with SiC leading to structure loosing which increases oxidizing damage ; Al （ g）, Al2 O （g） and CO （g） from refractories containing Al, Si and C react with SiC to form β-SIC and Al2O3, which leads to damage.

关 键 词：SiC加热元件 N2气氛 损毁机理 

分 类 号：TQ175.1[化学工程—硅酸盐工业]