Mechanical loss spectroscopy on inorganic glasses and glass ceramics

Abstract

While the classical mechanical loss studies on ion conducting glasses and glass ceramics were done with the help of torsional pendulums with relatively narrow frequency windows, there has been effort in the last years to make use of commercially available instrumentation for dynamic mechanical thermal analysis (DMTA) in order to perform mechanical loss spectroscopy over broader frequency ranges. This opens up the possibility to study in detail the frequency/temperature relations of mechanical losses caused by the ionic motions and so to learn more about the mechanisms of ion transport processes. Mixed mobile ion effects in different types of mixed mobile ion glasses, e.g. in mixed alkali glasses, mixed alkali alkaline-earth glasses, mixed alkaline-earth glasses, and mixed cation–anion glasses, have been studied by mechanical loss spectroscopy. Many of these effects are still poorly understood. In the theoretical description of the mechanical loss spectra of ion conducting glasses, first attempts have been made to use linear response theory in order to derive the mechanical loss of simple model systems from the microscopic dynamics of the mobile ions.