Short range ordering in Fe–Ge and Fe–Ga single crystals

We report on the nature of short range ordering (SRO) in slow cooled (100) and (111) Fe81.6Ga18.4 and Fe81Ge9 single crystals determined by x-ray θ-2θ scans. The SRO of the Ga atoms has at least some D03 character. In contrast Ge atoms only exhibit B2 chemical ordering symmetries in the short range order. It has been proposed that the D03 character in the SRO is important for the enhancement in magnetoelasticity in Fe-based alloys; however the presence of B2 character in Fe–Ge alloys suggest that the SRO is not of primary importance in increasing the magnetostriction.