X-ray diffraction studies of the structural activity of oxide glass melts during glass transition

摘要

GeO2 and a sodium aluminosilicate were studied by in-situ high-temperature X-ray diffraction measurements in a wide temperature range from ambient temperature up to temperatures above the liquidus temperature. In order to get information on how intensively the structure changes in the different temperature regions, the family of scattering curves was analyzed by a method based on simple statistical concepts. The overall structural activity of the melt and a specified structural activity, describing only qualitative changes, were determined. The latter function has a strong maximum slightly above T-g, indicating that glass forming begins with a rearrangement of structural units. (C) 2004 Elsevier B.V. All rights reserved.