Glass transition and viscosity in metallic glasses and liquids

Experimental results on the structure and dynamics of metallic liquids and glasses are most frequently discussed in terms of phenomenological theories, such as the free-volume theory and the mode-coupling theory. However, the atomistic bases for these theories have been lacking. We propose a more fundamental, microscopic approach that may fill this gap. It is based upon the concept of fluctuating topology of atomic bonds described in terms of the atomic-level stresses. While this approach is still under development, it already has enabled quantitative description of some of the properties of metallic glasses, including glass transition, viscosity and glass formation. (C) 2006 Elsevier B.V. All rights reserved.