Implementation of the UNIQUAC model in the OpenCalphad software

Jing Li, Bo Sundman, Jos Winkelman*, Antonis I. Vakis, Francesco Picchioni

*Corresponding author for this work

Research output: Contribution to journalArticleAcademicpeer-review

5 Citations (Scopus)
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The UNIQUAC model is often used, for example in engineering, to obtain activity coefficients in multicomponent
systems, while the CALPHAD method is known for its capability in phase stability assessment
and equilibrium calculations. In this work, we combine them by representing the UNIQUAC model according
to the CALPHAD method and implementing it in the OpenCalphad software. We explain the
harmonization of nomenclature, the handling of the model parameters and the equations and partial
derivatives needed for the implementation. The successful implementation is demonstrated with binary
and multicomponent phase equilibrium calculations and comparisons with literature data. Additionally
we show that the implementation of the UNIQUAC model in the OpenCalphad software allows for the
calculation of various thermodynamic properties of the systems considered. The combination provides a
convenient way to assess interaction parameters and calculate thermodynamic properties of phase
Original languageEnglish
Article number112398
Number of pages14
JournalFluid Phase Equilibria
Publication statusPublished - 1-Mar-2020

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