Calculation of the P-T phase diagram and tendency toward decomposition in equiatomic TiZr alloy
arXiv:1001.1700 · doi:10.1088/0953-8984/22/46/465401
Abstract
Electronic, structural and thermodynamic properties of the equiatomic alloy TiZr are calculated within the electron density functional theory and the Debye-Gruneisen model. The calculated values of the lattice parameters a and c/a agree well with the experimental data for the alpha, omega and beta phases. The omega phase is shown to be stable at atmospheric pressure and low temperatures; it remains energetically preferable up to T=600K. The alpha phase of the TiZr alloy becomes stable in the range 600K<T<900K, and the beta phase at temperatures above 900K. The constructed phase diagram qualitatively agrees with the experimental data available. The tendency toward decomposition in the equiatomic alloy omega-TiZr is studied. It is shown that in the ground state the omega phase of the ordered equiatomic alloy TiZr has a tendency toward ordering, rather than decomposition.
6 pages, 8 figures