Phase equilibria in Nb-Mo-rich zone of the Nb-Si-Mo ternary system

Abstract

Microstructures and phase equilibria in cast and annealed Nb-Mo-Si alloys near the Nb-Mo binary were studied using X-ray diffraction (XRD) analysis, scanning electron microscopy (SEM), and electron beam microprobe analysis (EPMA). A broad range of Nb and Mo compositions were investigated for Si compositions up to 30 mol%. Microstructural and microchemical evidence provide a clear definition of the Nb-Mo-Si liquidus surface projection and an isothermal section diagram at 1973 K.