First-Principle Calculation of the Effect of Ti Content on the Mechanical Properties of High Entropy Alloy AlFeTixCrZnCu

Abstract

Previous studies have shown that AlFeTiCrZnCu high entropy alloys (HEAs) are simple cubic crystal structure. In order to future study the effect of Ti content on high entropy alloys, the lattice parameter, mass density, elastic constant, elastic modulus, and the heats of formation for the high entropy alloys AlFeTi x CrZnCu with the different Ti content were studied by density functional theory of first principle and plane-wave pseudopotential technique with generalized gradient approximation (GGA). The crystal structure was built with the Virtual Crystal Approximation (VCA). The calculated results indicate that the lattice parameter of HEA AlFeTi x CrZnCu increases with the increasing mole fraction of Ti, and the mass density decreases. The mechanical stability of HEA AlFeTi x CrZnCu can be improved with the increase of Ti. The brittleness/toughness of HEA AlFe-Ti x CrZnCu also varies with the content of Ti or the brittleness/toughness criterion. The system stability and thermodynamic stability of HEA AlFeTi x CrZnCu did not change with the increase of Ti, but only decrease.