From closed-packed B3(Fe, Co, Ni)8 clusters to bulk metallic glass formation

Bulk metallic glasses are known to have a close relationship with some special clusters and can be designed within the framework of the cluster-plus-glue-atom model. So the key issue in applying this model lies in the determination of the appropriate clusters. In this paper, the atomic density radial distribution is proposed to define the closed-packed cluster. As examples B-Fe, B-Co and B-Ni alloy phases are analyzed from the viewpoint of coordination polyhedral clusters. Then capped octahedral antiprism B3(Fe, Co, Ni)8 clusters are highlighted because of the most close packing. Finally the relationship between B3(Fe, Co, Ni)8 clusters and bulk metallic glass formation is discussed and indeed verified by experiments.