A modeling investigation for pseudo-ternary (Ti,Mo,W)(CN) solid-solution: Thermodynamic and elastic properties

• Ti0.75(Mo1−xWx)0.25(C0.75N0.25) system was characterized by ordered-VCA models.
• Electronic structure calculations explained with this method works well.
• Calculated elastic moduli were consistent with experimental results.
• Computed free energy disclosed value of x as an increasing function of temperature.
• The amount of W in the most stable phase is found to increase with temperature.

We employ ordered-VCA (virtual crystal approximation) models to characterize [Ti0.75(Mo1−xWx)0.25](C0.75N0.25) pseudo-ternary system, using density functional theory, and compare the results with experiment. The ordered structure is found suitable to represent TiC-based solid solution systems. The chemical similarity of W and Mo is also noted in the calculations. The ordered-VCA models provide a good agreement with experimentally measured elastic moduli, and show the effect of nuclear charge number on the increase of elastic quantities. The ternary system becomes the most stable when x = 0.6. The value of x for the most stable phases increases with temperature.