Structures and physical properties of two magnetic Fe-based metallic glasses

Significant differences in structural, thermal, mechanical and magnetic properties were observed between traditional FeSiB metallic glass and newly developed FeMB (M = mixture of Zr, Nb and Y) metallic glass. The origin of the differences is attributed to the more negative heat of mixing between boron and the metallic alloying elements. This leads to the transition of local structure and bonding nature of FeB elucidated by the measured extended X-ray absorption fine structure (EXAFS) spectra functions that were analyzed employing ab initio multiple scattering calculations using the FEFF8.4 code and by the electronic structures of Fe as well. Such dramatic change sheds light on the understanding of the correlations between structure and physical properties in metallic glasses. The results were discussed based on electronic structures and they provide a new route to design magnetic Fe-based metallic glasses.