Structural analysis of amorphous Fe81-B19 alloy

The Fe81-B19 amorphous alloy was obtained by the roll quenching method, and the structure of this alloy was investigated by X-ray diffraction. The X-ray diffraction patterns of this amorphous alloy consist of halos. To analyze the halos patterns, characteristics of an amorphous structure, the interference function I(k) was calculated from the data of patterns. This function shows unsymmetric shapes of principal two peaks, and suggests the positions of nearly atoms are correlated within short range order only. The atomic distribution function W(r) was derived from I(k) using common Fourier analysis, then interatomic distances were obtained the radial distribution function (RDF) 4πr2γ(r) was calculated from W(r), and it gives the averge concentration of atoms as a function of distance from a reference atom. With this RDF, the obtained coordination number was about 11.5. These results were compared with Chen's about the atomic distribution of Fe-B amorphous alloys. (author)