| Abstract Scope |
In the aerospace, nuclear, and machining industries, alloys require high hardness and excellent wear-rate. Most high-performance alloys rely on cobalt for high-temperature properties, despite its political, ethical, and health concerns. Due to their intrinsic properties, high-entropy alloys (HEAs) offer pathways to substitute this critical element.
This study examines cobalt substitution in HEAs to optimize hardness and wear-rate. New alloys based on the Cantor alloy (CoCrFeMnNi) are produced by individually replacing cobalt with Al, V, Cu, and Mo. Four equiatomic HEAs (AlCrFeMnNi, CrFeMnNiV, CrCuFeMnNi, and CrFeMnMoNi) are compared with two literature alloys (Al0.2Co1.5CrFeNi1.5Ti and CoCrFeMnNi) and with the pure substituent elements.
The developed HEAs are multiphased and don’t mimic the structure of their corresponding pure element. CrCuFeMnNi differs from VEC predictions. Aluminum, vanadium, and molybdenum strengthen HEAs despite limited performances in their pure states. Ultimately, cobalt, CrFeMnMoNi, and AlCrFeMnNi display similar and lower wear-rate compared with the optimized reference alloy Al0.2Co1.5CrFeNi1.5Ti. |