Solid-solution like or nanoprecipitation like: the role of chemical short-range order in strengthening CoNiV

Using cross-confirmed characterization techniques, we unequivocally demonstrated the existence of V-centered CSRO in pure face-centered cubic CoNiVx alloys (x = 0.85-1.00), and correlated its average size with overall alloy strength. Notably, for x ≤ 0.95, CSRO is small (size ≤0.57 nm) and behaves like solid-solution atoms. This results in a strengthening trade-off between CSRO and solid-solution, providing only marginal strength increase with rising x. However, for x > 0.95, a sharp growth of CSRO to size over 0.72 nm enhances dislocation interaction, making CSRO alike shearable nanoprecipitates and causing a strength increment of over 50 MPa.