Thermodynamic and kinetic modeling of the Cr-Ti-V system

A synergistic approach of thermodynamic and kinetic modeling is applied to the Cr-Ti-V system. To assist the design of (α + β) and β titanium alloys for structural applications and vanadium alloys for fusion reactor applications, a set of self-consistent and optimized thermodynamic model parameters is presented to describe the phase equilibria of the Cr-Ti, Cr-V, Ti-V, and Cr-Ti-V systems. The Laves phases, α-Cr₂Ti, β-Cr₂Ti, and γ-Cr₂Ti, are described by a two-sublattice model assuming antistructure atoms on both sublattices. The calculated thermodynamic quantities and phase diagrams are in good accord with the corresponding experimental data. To assist the simulation of the kinetics of diffusional transformations in body-centered cubic (bcc) alloys, the atomic mobilities of Cr, Ti, and V are modeled. A set of optimized mobility parameters is given. Very good agreement between the calculated and experimental diffusivities was found.