Chemical short-range order in Fe50Mn30Co10Cr10 high-entropy alloy

Chemical short-range order (CSRO) is generally possible in concentrated solid solutions and currently of considerable interest for multi-principal element alloys. However, a convincing demonstration CSRO has been challenging achieved thus far only ternary medium-entropy alloys such as VCoNi. Here, we report definitive proof quaternary face-centered-cubic Fe50Mn30Co10Cr10 high-entropy alloy, acquired from systematic electron microscopy experiments. The evidence includes extra diffuse disks nano-beam diffraction patterns, images state-of-the-art aberration-corrected scanning transmission microscope, well compositional profiles across neighboring atomic planes/columns atomic-resolution chemical maps. regions are found to occupy an areal fraction 20% have dimensions on sub-nanometer scale. This length scale, the features CSRO, different those intermetallic compound precipitates; such, not growing stage nucleated second phase, precipitation which dealt with previously classical We further conducted spatial correlation analysis concentrations columns map, enabling us uncover general tendency toward nearest-neighbor ordering, specifically, preference unlike species (such Fe–Mn) avoidance like-species Fe–Fe). persistence this trend, same that VCoNi MEA, recently, somewhat intriguing alloy all constituent elements similar size rather small enthalpy mixing.