LAUSR

Abstract A thermodynamic reassessment of the ternary Ni–Si–Ti system was performed by means of CALPHAD (CALculation of PHAse Diagram) method. The fcc_A1/Ni 3 Si-L1 2 disordered/ordered transition was described using a four-sublattice model. The enthalpies of formation of the ternary compounds τ 1 , τ 2 , and τ 4 and end-members of the Ti 5 Si 3 and Ni 3 Ti phases at 0 K in the Ni–Si–Ti ternary system were computed via first-principles calculations to supply necessary thermodynamic data for the CALPHAD modeling. In the Ni–Si–Ti ternary system, it was clarified that the ordered Ni 3 Si-L1 2 phase is formed from the liquid phase with the addition of Ti. An optimal set of thermodynamic parameters for the Ni–Si–Ti system was obtained by taking into consideration of the experimental data from the literature and theoretic values from the present first-principles calculations. Comparisons between the calculated and measured phase diagrams indicated that almost all the reliable experimental information was satisfactorily accounted for by the present modeling.