Anup K. Gangopadhyay
Washington University in St. Louis, USA
Title: Fragility of metallic liquids manifest in the high temperature structure and cohesive energy
Biography
Biography: Anup K. Gangopadhyay
Abstract
Glasses are traditionally classified as “fragile” or “strong”, depending on the rates of change of dynamical properties (viscosity, diffusion coefficient) with temperature near the glass-transition temperature. It will be shown that the temperature dependence of viscosity far above the liquidus is an equally good measure of fragility. From the measurements of liquid structures of a large number of metallic glass-forming liquids using the electrostatic levitation (ESL) technique, combined with synchrotron x-rays, it will be demonstrated that the rates of structural changes of equilibrium and supercooled (metastable liquid below the liquidus) liquids with temperature are intimately connected with the liquid/glass fragilities. A strong connection between fragilities and average cohesive energies for metallic liquids will also be demonstrated.