THE LOCAL ATOMIC-STRUCTURE STUDY OF ORDERED FE3SI AND DISORDERED BY GRINDING FE75SI25 ALLOYS WITH EXAFS AND MOSSBAUER TECHNIQUES

The ordered Fe3Si and disordered Fe75Si25 alloys are studied by X-ray diffraction, Mossbauer spectroscopy and EXAFS-analysis. The X-ray diff raction pattern and Mossbauer spectrum of the Fe75Si25 alloy in compar ison with those of the ordered sample give evidence for the set of loc al atomic configurations of Fe atom and are characteristic for the dis ordered bce samples of the Fe-Si system. The comparison of chi(k) in t hese alloys shows noticeable differences, especially in 3.5-5 Angstrom (1)region. Combining all the data obtained with the model chi(k) One Can draw the conclusion that the changes in the Fe atom local structur e of the Fe75Si25 alloy are connected with breaking a long-range order but do not correspond to a chaotic distribution of atoms.