Enhancing the mechanical properties of casting eutectic high entropy alloys with Mo addition

Eutectic high entropy alloys (EHEAs) exhibit excellent mechanical properties in the as-cast condition. In this paper, Mo element was chosen to further strengthen the EHEAs by solid solution strengthening. The microstructures, phase compositions and mechanical properties of Co30Cr10Fe10Al18Ni32-xMox (x=0, 1, 2, 3) alloys were investigated. It was found that Mo acts as a solid solution strengthening element in the face-centered cubic (FCC) and body-centered cubic (BCC) phases. Meanwhile, Mo can promote the formation of the primary BCC phase. Among all alloys, the alloy with Mo (x=2) has the highest fracture tensile strength of 1250MPa and the acceptable elongation of 14%.