Application of phase diagram calculations to development of new ultra-high temperature structural materials

来源期刊：中国有色金属学报(英文版)2007年第6期

论文作者：杨莹 B.P. Bewlay 陈双林 Y.A. Chang

文章页码：1396 - 1404

Key words：intermetallics, phase diagram calculation; Mo-Si-B-Ti; Nb-Cr-Si-Ti; high temperature structural materials

Abstract: In-situ refractory metal intermetallic composites(RMICs) based either on (Nb, Si) or (Mo, Si, B) are candidate materials for ultra-high temperature applications (＞1 400 ℃). To provide a balance of mechanical and environmental properties, Nb-Si composites are typically alloyed with Ti and Cr, and Mo-Si-B composites are alloyed with Ti. Phase diagrams of Nb-Cr-Ti-Si and Mo-Si-B-Ti, as prerequisite knowledge for advanced materials design and processing development, are critically needed. The phase diagrams in the metal-rich regions of multicomponent Nb-Cr-Ti-Si and Mo-Si-B-Ti were rapidly established using the Calphad (Calculation of phase diagram) approach coupled with key experiments. The calculated isotherms, isopleths, and solidification paths were validated by experimental work. The important heterogeneous multiphase equilibria in both quaternary systems identified will offer engineers the opportunity to develop materials with a balance of properties for high-temperature applications.