Thermodynamic reassessment of Sn–Zr system assisted by DFT phonon calculations

The Sn–Zr system was re-assessed thermodynamically. Gibbs free energies of the intermetallic compounds of this system were calculated by DFT phonon calculations which can give more reliable information owing to considering the contributions of lattice vibration and electric thermal excitation. Newly published valuable experimental data of liquidus, solidus and invariant reactions of this system were used for the first time in the optimization of the model parameters. It is shown that the previous thermodynamic models, where the Gibbs free energies of formation at different temperatures were replaced by energies of formation at 0 K, overestimated obviously the stability of all the compounds of this system. The thermodynamic model for the Sn–Zr system established in this work would give more solid prediction of phase structures and thermodynamic properties for materials containing Sn–Zr system.