High-temperature internal friction peak and oxygen diffusion in Li_2O 2SiO_2 glass

摘要

A single alkali silicate glass exhibits two internal friction peaks: a low-temperature peak and a high-temperature peak. The low-temperature peak is caused by the stress-induced movement of alkali ions [1-4] because of the agreement between the activation energies for the low-temperature peak and for the alkali diffusion in the glass. The high-temperature peak has been variously attributed to cooperative action of two sodium ions [2], stress-induced movement of non-bridging oxygen ions [5-9] and so on [10-12]. Recently, the agreement between the activation energies for the high-temperature peak of alkali borosilicate glasses and for oxygen diffusion in these glasses has been reported [13, 14]; this shows that the high-temperature peak of alkali borosilicate glasses can be ascribed to the stress-induced movement of non-bridging oxygen ions. However, such agreement of the activation energies has not been reported concerning single alkali silicate glasses, although the causes of the high-temperature peaks of single alkali silicate glasses and alkali borosilicate glasses are thought to be identical [15].