X-ray diffraction studies of specific features in the atomic structure of Fe-Si alloys in the α area of the phase diagram

The atomic structure of Fe-Si alloys with a silicon concentration of 5–8 at % (α-area of the phase diagram) was studied using X-ray diffraction. The effect of quenching after annealing at a disordering temperature of 850°C on the structural state of the alloys was elucidated. It is shown that the quenched samples are characterized by a short-range ordering; namely, there is a local B2-type order at a concentration of 5–6 at % Si and, in addition, DO3-phase clusters are formed at 8 at % Si. The atomic structure of B2 clusters and their nearest surroundings is established.