Prediction of glass-forming compositions in metallic systems: copper-based bulk metallic glasses in the Cu-Mg-Ca system

A novel methodology for predicting specific compositions for glass-forming alloys based on efficiently packed atomic cluster selection, liquidus lines, and ab initio calculations is presented. This model has shown applicable adaptation to many known metallic and ceramic oxide glassforming systems and has led to the discovery of soon to be reported Ag-and Zn-based bulk metallic glasses (BMGs). As a model system, glass formation in the Cu-Mg-Ca ternary system has been assessed using this alloy design methodology, which has led to the discovery of a number of Cu-based BMGs with compositions ranging from Cu-33 to 55 at. pct, Mg-18 to 45 at. pct, and Ca-18 to 36 at. pct. Included in this work are the calculated values of associated cluster binding energies and correlations between physical and thermal properties of these glassy compositions, which show significant physical evidence to support the likely existence of such clusters.