Phase stability and elastic properties in the $Al_{1-x-y}Cr_{x}Ti_{y}N$ system from first principles

TL;DR

This study uses first principles calculations to analyze phase stability, magnetic, and elastic properties of $Al_{1-x-y}Cr_{x}Ti_{y}N$ nitrides, providing insights for designing hard coating materials.

Contribution

It offers the first comprehensive computational analysis of phase stability, magnetic transitions, and elastic properties of $Al_{1-x-y}Cr_{x}Ti_{y}N$ systems, guiding material design.

Findings

Magnetic transition from antiferromagnetic to ferromagnetic at TiN concentrations above 60%.

Lower aluminum solubility in the quaternary system compared to ternary systems.

Higher hardness predicted along the B1 to B4 phase transition line.

Abstract

Multicomponent nitrides are a hot research topic in the search of hard coatings. The effect of substitutions on the phase stabilities, magnetic, and elastic properties of $Al_{1-x-y}Cr_{x}Ti_{y}N$ $(0\leq x,y\leq1)$ was studied using first principles calculations based on the density functional theory. These calculations provide the lattice parameter, formation energy, mixing enthalpy and elastic constants. The calculated values are in good agreement with experiments and compare well with other theoretical results. A magnetic transition from antiferromagnetic to ferromagnetic state occurs at concentrations of B1-TiN higher than 60$\%$. The quaternary zone has a lower aluminum solubility than the constituent ternary systems. The Poisson's ratio, Shear and Young modulus were used as predictors of the hardness, indicating that the higher hardness values are found on the transition line from B1 to B4. The obtained results enable the design of new $Al_{1-x-y}Cr_{x}Ti_{y}N$-based materials for coating applications.