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arXiv · 0901.0200

Calculation of solubility in titanium alloys from first-principles

Roman V. Chepulskii·Stefano Curtarolo
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Abstract

We present an approach to calculate the atomic bulk solubility in binary alloys based on the statistical-thermodynamic theory of dilute lattice gas. The model considers all the appropriate ground states of the alloy and results in a simple Arrhenius-type temperature dependence determined by a {\it "low-solubility formation enthalpy"}. This quantity, directly obtainable from first-principle calculations, is defined as the composition derivative of the compound formation enthalpy with respect to nearby ground states. We apply the framework and calculate the solubility of the A specie in A-Ti alloys (A=Ag,Au,Cd,Co,Cr,Ir,W,Zn). In addition to determining unknown low-temperature ground states for the eight alloys, we find qualitative agreements with solubility experimental results. The presented formalism, correct in the low-solubility limit, should be considered as an appropriate starting point for determining if more computationally expensive formalisms are otherwise needed.

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Roman V. Chepulskii, Stefano Curtarolo. 2009-01-01. Calculation of solubility in titanium alloys from first-principles. https://doi.org/10.1016/j.actamat.2009.07.037

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