Thermodynamic optimization and phase equilibria in the ternary system Ni–Sn–Zn

[Display omitted] •Thermodynamic description of the Ni–Sn–Zn system was obtained.•Six isothermal sections were calculated.•Third constituents solubility in binary phases’ extensions were taken into account.•Good correlation between calculated and experimental data was obtained. Recent experimental results obtained by differential scanning calorimetry, Scanning Electron Microscopy and other methods were used to develop a thermodynamic description of the ternary system Ni–Sn–Zn. Four ternary non-stoichiometric compounds (T1–T4), mentioned in the literature, were described using three-sublattice models. Previously known optimizations of the binary subsystems were remodeled to comply with the new experimental data. The solubility of the respective ternary components, i.e., Zn in Ni–Sn phases and Sn in Ni–Zn phases, were taken into account and optimized ternary parameters were derived. Six isothermal sections were calculated using Thermo-Calc software.