Enhanced bulk metallic glass formability by combining chemical compatibility and atomic size effects

The glass formability (GFA) of Y- and Ca-based alloys is enhanced by inserting elements that yield a more uniform separation in the atomic sizes, as well as a wider atomic size distribution range, in agreement with the analytical findings of Miracle, Senkov, and others. The degree of the GFA improvement depends on the chemical compatibility of the addition elements with the existing components. By combining this observation with similar results noted in other alloys that form large-size bulk metallic glasses, the importance of the atomic size effect and chemical compatibility in glass forming alloys is revealed. The atomic size effect and chemical compatibility are discussed along with other glass forming factors. (C) 2004 American Institute of Physics.