铌硅化物基超高温合金与石墨坩埚氧化物涂层反应的热力学分析  

Thermodynamic Analysis of the Reaction of the Nb Silicide-based Superalloys with Oxide Coatings for the Graphite Crucibles

作　　者：吴梅柏[1] 郭喜平[1] 

机构地区：[1]西北工业大学凝固技术国家重点实验室,陕西西安710072

出　　处：《稀有金属与硬质合金》2007年第1期5-9,13,共6页Rare Metals and Cemented Carbides

基　　金：国家自然科学基金项目(50271056);教育部新世纪优秀人才支持计划项目资助

摘　　要：利用热力学计算,分析了几种氧化物涂层Y2O3、ZrO2、Al2O3、MgO、CaO、Ce2O3和BeO等在高温下与新型铌硅化物基超高温合金中的几种主要元素Nb、Si、Ti和Hf之间反应的可能性,得到了这些反应的ΔG与温度T的关系图。通过比较这几种氧化物对合金熔体在高温下的化学稳定性,发现Y2O3和BeO对这些合金元素的化学稳定性较好,且Y2O3为熔炼铌硅化物基超高温合金用石墨坩埚的理想涂层材料。Thermodynamic calculation is made to analyze the possible reaction of Y2 O3, ZrO2, Al2 O3, MgO, Cao,Ce2O3 and BeO with the main elements Nb,Si,Ti and Hf of the new Nb silicide-based superalloys at high temperature. The curve of relationship between △G^- and temperature T for those reactions is obtained. Through analyzing and comparing the chemical stability of several oxides with the melt of Nb silicide-based superalloys,it is found that both Y2 O3 and BeO are chemically stable to these alloy elements at high temperature,and Y2O3 is well suitable for the coating of graphite crucibles to melt Nb silicide-based superalloys.

关 键 词：铌硅化物基超高温合金 石墨坩埚 氧化物涂层 热力学分析 

分 类 号：TG164.4[金属学及工艺—热处理]