| Abstract Scope |
High entropy alloys (HEAs) are promising materials known for their excellent strength, ductility, and thermal stability under extreme conditions. In this study, we developed an ultrastrong, six-element dual-phase HEA with high specific strength, using analytical models and CALPHAD. The alloy composition, selected from a pool of Al, Ti, Sc, V, Cr, Fe, Co, Ni, Cu, Nb, and Mo, was produced by vacuum arc melting. X-ray diffraction (XRD) confirmed a dual-phase structure of ordered B2 and L12 phases. Detailed crystal structure and microstructure were analyzed using SEM/EDS, TEM, SADP. A eutectic structure consisting of B2 and L12 phases was confirmed and characterized by HAADF and STEM-EDS. Mechanical testing demonstrated a microhardness of 630 HV and an ultimate compressive strength exceeding 2500 MPa. Fracture analysis revealed a mixed-mode failure mechanism, where the dimples were attributed to the eutectic with the L12 phase, while cleavage was associated with the B2 dendritic regions. |