Effect of alloying on the thermal-elastic properties of 3d high-entropy alloys

Using the quasi-harmonic approximation in combination with ab initio calculations, we study the temperature dependent elasticity of single-phase face centered cubic (fcc) Co-Cr-Fe-Mn-Ni multi-principle element alloys. Results suggest that the addition of an equimolar alloying element increases the fcc stability due to the increasing valence electron concentration of alloys. The ductility of paramagnetic alloys becomes superior with the increase of temperature. For the CoCrFeMnNi high-entropy alloy, the Young's moduli along different crystal directions are consistent with experiments. The difference between ab initio predicted temperature dependent elastic moduli and experiments is discussed.