Consideration of cluster and state density of electrons during design of stable amorphous alloys

It has been attracting scientists to know what factors control the glass forming ability in metal alloy systems since Inoue reported the first stable amorphous alloy with large super-cooling liquid region. Several models have been proposed, most are based on empirical rules. Here we present a design idea, in which a cluster in amorphous is constructed referring to composition and structure of crystal precipitated from amorphous when heated, then density of states at the Fermi level of the above cluster is calculated by local density functional theory. The Zr–Cu system was selected. By constructing different clusters and substituting Cu in the cluster by Al atoms, the glass forming ability is analyzed with different Al addition. It is found that the selection of clusters’ configuration is very important, when an Archimedes antiprism of cluster for Zr–Cu system was selected. Calculated results agree well with the experimental ones.