摘要
铌及铌硅化合物具有优良的力学性能,可替代现有的镍基合金超高温材料。通常,这类材料的高温抗氧化性能较差,铌在高于350℃时即发生剧烈氧化,而抗氧化性能较好的NbSi2在1000K附近也会出现"pest"现象。铌硅化物的氧化行为与钼(或钨)硅化物存在很大区别,其氧化产物无挥发性。通过增加硅的含量,或添加钛、铝、铬等元素,涂敷高温抗氧化涂层等,可有效提高铌及铌硅化合物的高温抗氧化能力。
Niobium and niobium silicides due to their good mechanical properties, have high potential for being the high-temperature materials as a substitute for nickel alloys. In general, the oxidation resistance of those materials at high temperatures is poor. Niobium will be severely oxidized at temperatures higher than 350℃, and even NbSi_2 will araise the 'pest' at 1 000K. The oxidation behavior of niobium silicides is quite different from that of molybdenum (or tungsten) silicides, for the oxidation products of niobium silicides have no volatility. Increasing the content of silicon, or adding Ti, Al, Cr and other elements, the high-temperature oxidation resistance of niobium and niobium silicides can be improved. Using oxidation-protective coating is also an effective way to protect the materials from oxidation.
出处
《机械工程材料》
CAS
CSCD
北大核心
2003年第12期1-3,31,共4页
Materials For Mechanical Engineering
基金
国家自然科学基金资助项目(50131030)
上海应用材料研究与发展基金资助项目(0211)
