Glass-formation and crystallization processes in Ag-Y-Cu alloys

Investigation of glass-formation and crystallization processes of several alloys of Ag-Y-Cu system was conducted. The samples were produced by melt spinning and Cu-mold casting. The structure of ribbon samples was examined by X-ray diffractometry and transmission electron microscopy. Phase transformations were studied by differential scanning and isothermal calorimetry and differential thermal analysis. Despite the large difference in atomic radii between the components in the investigated system, even being produced by melt spinning technique at high cooling rate, only Ag61Y29Cu10 alloy with large supercooled liquid region was found to be X-ray amorphous. A principle for obtaining an alloy with high glass forming ability involving difference in atomic radii between the alloy components is considered. Efficient cluster packing model was also tested. (C) 2012 Elsevier B.V. All rights reserved.