•The enthalpies of formation for all intermetallic compounds were computed.•A set of more accurate thermodynamic parameters was obtained.•Better agreement with experimental data compared to previous Calphad work.Based on the available experimental phase equilibria and thermodynamic data and enthalpies of formation computed via first-principles calculations, thermodynamic reassessment of the Au–Dy system was carried out by means of the CALPHAD method. The enthalpies of formation at 0 K for AuDy2, αAuDy, βAuDy, Au2Dy, Au3Dy, Au51Dy14 and Au6Dy were computed via first-principles calculations to supply the necessary thermodynamic data for the modeling in order to obtain the thermodynamic parameters with sound physical meaning. The solution phases, i.e. liquid, (Au), (αDy) and (βDy), were described by the substitutional solution model, and all the intermetallic compounds in the Au–Dy system were treated as stoichiometric phases. A set of self-consistent thermodynamic parameters for the Au–Dy system was finally obtained. The calculated phase diagram and thermodynamic properties agree reasonably with the literature experimental data and the present first-principles calculations.

•Structure, elasticity and thermal decomposition of Ti1 − xTMxN were studied.•We predicted the alloying effects on spinodal decomposition of Ti1 − xTMxN.•Consulate temperatures of Ti1 − xTMxN miscibility gaps were evaluated.•Addition of Nb and Ta increases the ductility, with Ta possessing the largest effect.A systematic investigation concerning the effects of transition metals (TM = Y, Zr, Nb, Hf, and Ta) on the structure, elasticity and thermal decomposition of the TiN-based nitride coatings with a cubic rock-salt structure has been performed in terms of first-principles calculations. Calculated lattice parameters of Ti1 − xTMxN as a function of alloying concentration show positive derivations from the linearized Vegard's law, agreeing well with experimental and theoretical results. Positive enthalpies of mixing of Ti1 − xTMxN (TM = Y, Zr, and Hf) indicate that the formation of these alloys is energetically unfavored with respect to the mixing of the cubic phases. The predicted consolute temperature of Ti1 − xZrxN agrees reasonably well with previous theoretical findings. The miscibility gaps disappear in the case of alloying TiN with NbN and TaN. Predicted elastic stiffness constants C11, C12, and C44 together with the aggregate polycrystalline properties of Ti1 − xTMxN are determined by an efficient strain–stress method. The present results indicate that the above nitride alloys are mechanically stable and addition of Nb and Ta increases the ductility, with Ta possessing the largest effect.