Characterise structures of bulk metallic glasses

Structures of amorphous Zr-based and Fe-B-based bulk metallic glasses are discussed in comparison with those for conventional amorphous alloys. One of the main concern on the metallic glasses is the origin of structural stability. On annealing, they show a clear glass transition before crystallization and transform into supercooled liquid. The amorphous Zr-based alloys have been attracted the great attention because they consists of only metallic elements. Structural studies by diffraction techniques revealed that their structures are characterized by icosahedral clusters. Similar structural studies in the amorphous Fe-Nb-B alloys using the reverse Monte-Carlo method in combination with diffraction measurements also indicate that the presence of densely packed atom clusters formed around Nb is a key role for the structural stability.