A comparison of structural measurements of Fe-B metallic glasses

Abstract

A comparison has been made between two recent, independent X-ray determinations of the structure of Fe-B metallic glasses which are in disagreement. The structure factors for two similar Fe-B glasses obtained in these two studies have been critical compared, and their differences discussed. The effect which these differences in S(Q) have on the reduced radial distribution function G(r) has then been examined in a systematic way. It is suggested that some of the disagreements in the S(Q) curves can arise through structural differences in the samples, which are related to their state of quench. In addition it is shown that errors in the experimental method and systematic variations in data analysis can also influence the form of S(Q) in a similar way, and hence affect G(r). A conclusion reached from this comparison is that the second peak splitting in G(r) appears to be too susceptible to experimental uncertainty to be considered an important characteristic of metallic glass structure. Finally it is suggested that an adequate treatment of chemical as well as topological order is needed in order that reliable structural data may be obtained for these transition metal-metalloid glasses.