铌酸铝/莫来石复合陶瓷环境阻障涂层高温水蒸气腐蚀行为研究(英文)  

Corrosion Behavior of AlNbO_4/Mullite Composite as Environmental Barrier Coating in Water Vapor Environment

作　　者：吴疆[1] 林红[1] 李建保[1] 李俊峰[1] 

机构地区：[1]清华大学材料科学与工程系新型陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《无机材料学报》2010年第4期445-448,共4页Journal of Inorganic Materials

基　　金：National Basic Research Program of China(973,2007CB607504);National High Technology Research and Development Program(863,2007AA03Z524);National Natural Science Foundation of China(50672041)

摘　　要：利用大气等离子喷涂的方法在氮化硅基底上制备了铌酸铝/莫来石复合陶瓷环境阻障涂层.铌酸铝的含量为5mol%.涂层置于1400℃下含有50vol%H2O和50vol%Air的气氛中进行侵蚀实验.总压力1×105Pa,实验时间100h.研究表明:铌酸铝可以在涂层表面形成玻璃相保护层,提高了涂层在高温水蒸气环境中的耐蚀性.然而与氮化硅基底之间的热膨胀系数差异会造成涂层在实验过程中发生轻微剥离的现象,导致试件的失重增加.AlNbO4/mullite composite environmental barrier coating（EBC） with 5mol% AlNbO4 content was prepared on Si3N4 substrate by atmospheric plasma spraying（APS）.There was evidence that the weight loss rate of Si3N4 substrate coated by AlNbO4/mullite composite was less than that of Si3N4 substrate coated by mullite during the first 50h corrosion test.The improved protective capacity of AlNbO4/mullite composite coating was ascribed to the formation of glassy AlNbO4 top surface.After 100h corrosion test,the AlNbO4/mullite coating was still stable and no further corroded cavities were observed.However,slight delamination of the coating and a faster weight loss rate was observed after long time corrosion due to the coefficient of thermal expansion（CTE） mismatch between AlNbO4/mullite composite and Si3N4 substrate.

关 键 词：莫来石 铌酸铝 环境阻障涂层 水蒸气侵蚀 

分 类 号：TQ174[化学工程—陶瓷工业]