Phase Equilibria in the Be-V and Be-Ti Binary Systems

摘要

Phase equilibria in the Be-V and Be-Ti binary systems are investigated. Be-(5-25)at.%V and Be-(5-23)at.%Ti alloys prepared by arc melting were equilibrated at 1200, 1350 and 1450℃. Liquid/solid diffusion couples of Be/V and Be-70at.%Ti/Be were annealed at 1350℃ and 1100℃, respectively. Backscattered electron (BSE) images of as-cast and annealed microstructure were examined and equilibrium composition of multi-phase alloys and composition profiles in the diffusion layers were measured by EPMA. Eutectic, peritectic and peritectoid invariant reactions were identified from the as-cast microstructures and equilibrium composition was determined on the annealed alloys and diffusion couples. Phase diagrams of the Be-V and Be-Ti binary systems are obtained.