Generalized stacking fault energies, ductilities, and twinnabilities of CoCrFeNi-based face-centered cubic high entropy alloys

Abstract

Effects of Cu, Mn, Al, Ti, Mo on generalized stacking fault energies, Rice-criterion ductilities, and twinabilities of CoCrFeNi-based face-centered cubic high entropy alloys were investigated using density functional theory calculations. The calculated barrier energies and twinnabilities revealed that the addition of Ti or Mo increased the tendency of dislocation glide and deformation twinning, while addition of Mn, Cu and relatively high amount of Al facilitated dislocation gliding and martensitic transformation. Low amount of Al resulted in only dislocation gliding. Furthermore, the addition of Mn and Cu increased the calculated Rice-criterion ductility while other elements decreased it.