Enhanced strength-ductility synergy in a novel V-containing γ″-strengthened CoCrNi-based multi-component alloy

Highlights: • γ″ phase is successfully introduced in the CoCrNi-based medium entropy alloys. • The precipitation of γ″ causes a significant enhancement in strength. • V-addition overcomes strength-ductility trade-off in γ″-strengthened alloys. • Synchrotron X-ray diffraction is used to identify γ″/γ lattice misfit. γ″ precipitates have been introduced into V-containing CoCrNi-based alloy, showing superior strength-ductility synergy (product of ultimate-tensile-strength and elongation ~51.8 GPa·%, yield-strength ~890.6 MPa) than reported γ″-strengthened and CoCrNi-based alloys. Synchrotron XRD was first-time used to identify the existence of γ″ phase in V-containing CoCrNi-based alloys, where moderate γ″/γ lattice misfit results in good combination of coherency-strengthening and coarsening-resistance.