Effect of thermal treatment on the short-range order in Fe-Cr alloys

Distribution of Cr atoms in Fe1−xCrx studied with the Mössbauer spectroscopy was shown to be characteristic of neigbor shell, and, to lesser extent, of heat treatment. SRO-parameter averaged over the first-two neighbor shells, 〈α12〉, in quenched samples was slightly positive or close to zero for x<∼0.14, and more positive at higher x-values. In isochronally annealed samples 〈α12〉 followed the trend predicted by MC simulations [PRB 77, 134206 (2008)]. Clear-cut segregation induced by an isothermal annealing at 415 °C was found for Fe0.85Cr0.15.