Upscale Production and Characterization of the Cr40Co30Ni30 Multiprincipal Element Alloy

Abstract

Multiprincipal Element Alloys (MPEAs) represent a new category of metallic alloys that stand out for exclusively containing solute elements in equiatomic/nearly equiatomic proportions in their composition. Due to their remarkable mechanical properties, these alloys have garnered significant interest within the scientific community. However, one of the major challenges associated with these alloys is their industrial-scale production. Therefore, this study aims to evaluate production and processing routes for obtaining MPEAs on an upscale, i.e., with masses on the order of several kilograms. To achieve this goal, we produced the Cr₄₀Co₃₀Ni₃₀ alloy (at. pct) using a vacuum induction furnace (VIM), resulting in ~ 50-kg ingots. Subsequently, the samples underwent hot forging and rolling processes, followed by analyses of composition and inclusion formation. The presence of Cr and Al oxide inclusions in the samples was observed in both samples. The composition remained homogeneous throughout the ingot’s cross-section. However, the forging process proved ineffective and resulted in several cracks during the procedure. On the other hand, hot rolling proved a more viable process, also promoting dynamic recrystallization, although crack formations also occurred. In both processes, as well as in the casting, the formation of the sigma phase was not observed.