Research on bulk metallic glasses is one of the red-hot areas in the field of Materials Science because of the great scientific and technological importance of these prominent materials. In the design of these novel materials, properly predicting glass-forming ability—i.e., how easily a material can form glass—for various alloy systems, is extremely crucial and urgently needed. Our paper provides a new and reliable criterion which can be easily quantified for representing glass-forming ability in bulk metallic glasses.

Our paper describes a new methodology to reflect the relative glass-forming abilities of various alloy systems regardless of their actual compositions. With the use of this new criterion, the critical cooling rate for glass formation and maximum attainable sizes can be estimated, which offers useful guidelines for searching new bulk metallic glasses.

In the design of new bulk metallic glasses, a simple but reliable indicator, which can judge how easily an alloy can form amorphous structure without any crystallization, is demanded. However, there is no such reliable gauge available in the literature. We have solved this problem by suggesting a new criterion for glass formation with considerations of both crystallization resistance and liquid phase stability. The related physical insights of this new criterion were explicitly elaborated in one of our later publications [Physical Review Letters, 91: 115505, 2003]. As a result, a new parameter showing better correlation with glass-forming ability than all existing indicators prevailingly utilized by the field is obtained.

Understanding the nature of bulk glass formation and establishing scientific principles for designing new bulk metallic glasses are one of the focused areas of our group at the Oak Ridge National Laboratory. We became interested in non-precious-metals-based bulk metallic glasses immediately after they were first reported in the 1990s.