Composition formulae of ideal metallic glasses and their relevant eutectics established by a cluster-resonance model.

Composition formulae for ideal metallic glasses are explored by combining the cluster-plus-glue-atom model with the global resonance model, termed the cluster-resonance model for short. The former model gives the [cluster]1(glue atom)x cluster formulae, stressing the local cluster order of a glassy structure; the latter model extends the local cluster order to a medium-range one by introducing spherical periodicity that relates the cluster size with Fermi vector, kF. Such a correlation allows the calculation of Fermi energy, EF, and electrochemical potential of electrons of the system from any local clusters. The cluster-resonance model also implies the equilibrium of the electrochemical potentials of electrons between different clusters so that the number of glue atoms matching one cluster (x in the cluster formula) can be determined. Examples in the Cu-Zr-Al and B-Co-Si-Ta systems are given to show the effectiveness of the proposed model and the resulting cluster formulae in interpreting multicomponent metallic-glass compositions as well as their relevant binary eutectic points. [ABSTRACT FROM AUTHOR]