The effect of the partial substitution of Al for Ag in the glass forming ability (GFA) of the Zr57.52Co21.24Al21.24-xAgx (x = 8, 10, 12, and 14 at. %) family alloy are reported and discussed. Cylindrical and conical ingots were obtained using the suction casting technique. It was found that the Zr57.52Co21.24Al9.24Ag12 alloy showed a glassy structure, with a critical glassy diameter, Dc, of 2 mm and ∆Tx = 41 K. The bulk metallic glass Zr57.52Co21.24Al9.24Ag12 alloy was examined using scanning electron microscopy, differential thermal analysis and mechanical compression test. This alloy showed a Young´s modulus (E) of 76.4 GPa and yield strength (σy) of 1.58 GPa. The Glass Forming Ability of the Zr57.52Co21.24Al9.24Ag12 was explained in terms of the topological model of dense packed clusters and kinetic fragility index of the alloy.

The results of database based on the efficiency packed model for metallic glasses. The database contains the atomic radii information as well as elastic properties of the most commonly used alloying elements, permitting composition, packing efficiency and elastic property predictions to be made for binary, ternary and quaternary bulk metallic glasses. Twenty different alloys per system (binary, ternary and quaternary) experimentally reported in the literature were compared with those estimated by the database. Comparison charts and diagrams showed good agreement between the composition predictions and those reported from the experimentally processed metallic glasses. The elastic properties predictions could be used to elaborate Blackman diagrams in order to know, in advance, the intrinsic toughness that the investigated alloys might present. The database is intended for designing bulk metallic glasses. Finally, some quaternary alloys were experimentally produced based on the prediction obtained with the database, showing a glassy phase. The microhardness values obtained experimentally of the Zr57.52Ag10.62Al10.62Co21.24, Zr57.19Al10.7Ni10.7Cu21.41 and Hf60.22Al9.95Cu9.95Ni19.89alloys, are 3.8, 4.0 and 3.6 GPa, respectively. The Young´s modulus calculated using microhardness values (E/Hv = 20) are closed to the values obtained by the "mixing rules".