Partial Substitution of Mn by Al in the Cocrfenimnxal20-X (X=5, 10, 15) High Entropy Alloy Prepared of Mechanical Alloying and Spark Plasma Sintering

Abstract

High-entropy alloys are known to possed good mechanical properties which are usually related to the preparation technique. In this work, the CoCrFeNiMnXAl20-X (X=5, 10, 15) alloys were prepared by a combination of mechanical alloying (MA) and com-pacted via spark plasma sintering (SPS). Such prepared materials were examined for their phase composition and microstructure. Furthermore, their mechanical properties as a result of the content of Mn/Al were determined. It was found, that the partial substitution of Mn by Al lead to increasing the volume content of the solid solution with BCC crystallographic lattice within the ultrafine-grained microstructure of such prepared materials. Moreover, increasing the Al content within the alloy lead also to the improvement of the mechanical properties. The CoCrFeNiMn5Al15 alloy reached the best properties of all the alloys showing compressive strength of 2496 MPa and having a hardness of 668 HV 1.