Glass Forming Ability and Mechanical Properties of Zr_57.52Co_21.24Al_9.24Ag₁₂ bulk metallic glass

The effect of the partial substitution of Al for Ag in the glass forming ability (GFA) of the Zr_57.52Co_21.24Al_21.24-xAg_x (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 Zr_57.52Co_21.24Al_9.24Ag₁₂ alloy showed a glassy structure, with a critical glassy diameter, D_c, of 2 mm and ∆T_x = 41 K. The bulk metallic glass Zr_57.52Co_21.24Al_9.24Ag₁₂ 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 (σ_y) of 1.58 GPa. The Glass Forming Ability of the Zr_57.52Co_21.24Al_9.24Ag₁₂ was explained in terms of the topological model of dense packed clusters and kinetic fragility index of the alloy.

Keywords:
Metallic glass; fragility index; packing efficiency; glass formation