Icosahedral Clusters and Composition Rules for Zr-based Bulk Metallic Glasses

摘要

In this paper, we will describe the formation rules of Zr-based bulk metallic glasses, originally developed for quasicrystals, by combining cluster structures with phase diagram features. We will introduce the e/a-constant and e/a-varianl criteria for ternary systems, and e/a-constant and atomic size constant criteria for quaternary systems. We will show how the glass forming composition optimization is realized by applying these rules in the Zr-Al-Ni and Zr-Al-Ni-Cu systems. In both systems the optimized glass-forming composition is related to a common binary icosahedral cluster Zn,Ni4 derived from the fee Zr3Ni phase.