|About this Abstract
||Materials Science & Technology 2019
||Phase Transformations in Ceramics: Science and Applications
||Investigations on the Glass Transition and Crystallisation Behavior of Glasses by Oscillatory Rheometry
||Christopher Giehl, Mario Kleindienst, Daniela Ehgartner
|On-Site Speaker (Planned)
The influence of heating and cooling rates, as well as the time-dependent relaxation behavior, are well-known processes related to the glass transition temperature. However, understanding of the energetic processes occuring near the glass transition and their thermodynamic or kinetic nature are an ongoing matter of debate. We here present quantitative mechanical data on the visco-elasticity of glasses near the glass transition temperature obtained from high temperature oscillatory rheometry. Such measurements provide the relative contributions of viscous and elastic moduli and provide insightful information on the strong or fragile character of glass melts. Frequency-dependent measurements allow to derive relaxation time spectra and the deformation-dependent isothermal glass transition. Furthermore, data from oscillatory measurements are capable to monitor the behaviour of metastable glasses, e.g. for unwanted crystallization or production of glass-ceramics.
||Definite: At-meeting proceedings