Compositional Dependence of Glass Formability in Al-Ni-Fe-Gd Amorphous Alloys

摘要

The Al-Ni-Fe-Gd quaternary glass-forming system has been mapped with respect toglass formability. This ability, as measured by the maximum amorphous ribbon thickness obtainable by a given rapid-solidification technique, is highly localized. Two ratios in the proportions of alloying elements are associated with maximum glass-forming ability, and these symmetries appear to hold across different solvent atom concentrations and may even hold across different A1-TM1-TM2-RE systems entirely. The densities of the alloys with these two types of symmetry, measured before and after induced crystallization, suggest that they have significantly different packing densities in the amorphous phase. It is suggested that unique interactions between certain pairings of transition metal and rare earth elements may be associated with the glass-forming abilities of particular Al-TM-RE ternaries and quaternaries.