Theoretical investigation of Co-dependence in magnetic high-entropy alloys

Abstract: High-entropy alloys (HEA) is a class of materials consisting of multiple principal elements that often crystallize in simple lattices such as body-centered cubic, face-centered cubic and hexagonal close-packed structures. Many HEAsexhibit exceptional mechanical properties, e.g., impact toughness and ductility at cryogenic temperatures and high temperature creep strength. Out of the known magnetic HEAs, the Cantor alloy, consisting of equalparts of Co, Cr, Fe, Mn, and Ni, is by far the most investigated. The influenceof magnetism on the stability and mechanical properties for these alloys isintricate and very interesting for that reason. The concentration dependencein this alloy is, however, fairly unexplored and it would be beneficial if onecould avoid including critical elements such as Co. As such, the purpose of this work was to find a suitable replacement forCo in the Cantor alloy. Using density functional theory, the Co-concentrationwas investigated by replacing Co with the other constituent elements in different ways. It was discovered that the most energetically stable configurations,with magnetic and structural properties similar to the equiatomic alloy, werefound in the body-centered cubic phase when replacing Co with Fe.