Short-range ordering of the alpha-Fe-Si single crystals

X-ray diffraction was used to study short-range ordering in iron alloys con taining 4.9 and 5.8 at. % silicon after thermomechanical treatment (TMT) re sulting in the formation of induced magnetic anisotropy. The data obtained confirm the Neel assumption of directed ordering of silicon atoms as a caus e for magnetic anisotropy. Within the measurement accuracy, no D0(3)-type s uperstructure, which was observed in the works of other authors in the allo ys containing 7% Si and more, is present in the alloys used. Instead, super lattice diffuse reflections that correspond to the ordering with the format ion of the B2-type structure and are weaker than the reflections of the fun damental bcc structure by 5-6 orders of magnitude were observed. The dimens ion of the ordered regions in the direction of the application of a dc magn etic field upon TMT is somewhat larger than that in the transverse directio n and reaches about 10 Angstrom. In addition, the fundamental bcc reflectio ns in the directions parallel and perpendicular to the magnetization direct ion upon TMT were established to substantially differ in width. No superstr ucture was observed in the silicon-free iron sample.