Local structural disorder introduced by Cr in fcc high-/medium-entropy alloys consisting of 3d transition metal elements

High-/medium-entropy alloys (H/MEAs) have attracted attention for their excellent mechanical properties. According to first-principles calculations, the atomic displacements from their lattice points are element-dependent and correlated with the yield strength of H/MEAs. To investigate experimentally the element dependence of the local structure, we measured the extended x-ray absorption fine structure in seven kinds of face-centered cubic H/MEAs consisting of 3d transition metal elements. Our experimental results indicate that the local disorder around chromium (Cr) is larger than that around other elements, which is a common feature in all the measured fcc H/MEAs, aligning with prior theoretical studies indicating larger displacements of Cr in comparison to other elements. We discuss the mechanism underlying the local structural disorder induced by the constituent element Cr.