The effects of the fabrication and heat - treatment methods on the microstructures and properties of the nb - si system intermetallics have been studied and the optimized nb - si intermetallic system as well as the optimized fabrication and processing procedures have been selected . the presence of alloying elements as well as the morphology and microstructure of the compound phases with these elements has been investigated . the effects of the alloying elements on the high - temperature oxidation behavior of the nb - si system intermetallics have also been studied 本文研究了不同的制备工艺和热处理制度对nb - si系金属间化合物显微组织和性能的影响，优选了合适的材料体系、制备工艺和热处理制度，分析了微合金化元素及其形成相的组织、结构、形态、存在形式等及其对材料高温抗氧化行为的影响，提出了材料高温抗氧化行为和室温断裂行为的微观机制，为研制nb - si系金属间化合物基高温结构材料奠定了一定的基础。
