Atomic origin of minor alloying element effect on glass forming ability of metallic glass

The glass-forming ability (GFA) of metallic glasses is a key scientific challenge in their development and application, with compositional dependence playing a crucial role. Experimental studies have demonstrated that the addition of specific minor elements can greatly enhance the GFA of parent alloys, yet the underlying mechanism remains unclear. In this study, we use the ZrCuAl system as a model to explore how the addition of minor Al influences the crystallization rate by modulating the properties of the crystal–liquid interface, thereby affecting the GFA. The results reveal that the minor addition of Al significantly reduces the crystal growth rate, a phenomenon not governed by particle density fluctuations at the interface. The impact of minor element additions extends beyond a modest increase in crystal-unfavorable motifs in the bulk supercooled liquid. More importantly, it leads to a significant enrichment of these motifs at the crystal-supercooled liquid interface, forming a dense topological network of crystal-unfavorable structures that effectively prevent the growth of the crystalline interface and enhance GFA. Our results provide valuable insights for the design and development of high-performance metallic glasses. © 2025 Chinese Physical Society and IOP Publishing Ltd. All rights, including for text and data mining, AI training, and similar technologies, are reserved.