Achieving superior strength–ductility synergy in refractory high entropy alloy

In contrast to the successful realization of strength-ductility synergy through local chemical ordering (LCO) in FCC systems, achieving similar effects in BCC structures remains challenging. The complex core structure of BCC dislocations leads to an opposite hindrance effect of LCO on screw dislocations compared to FCC systems, necessitating compositional design to optimize LCO distribution and morphology. Guided by the negative enthalpy alloy design philosophy, this study introduces high-density LCO in the V950 alloy. By modulating the synergistic interaction between LCO and texture, the alloy achieves exceptional mechanical properties, including ultrahigh yield strength (∼960 MPa), ultimate tensile strength (1159 MPa), and fracture elongation (∼27.5 %), surpassing most reported refractory high-entropy alloys (RHEAs). Furthermore, this work elucidates novel mechanisms of work hardening behavior in BCC-structured alloys, advancing fundamental understanding and design strategies for high-performance BCC systems.