Phase Separation In A Glass Melt With The Composition 6.5Na0.33.5B203.60Si02 Studied By Impedance Spectroscopy

A glass with the composition 6.5Na2O.33.5B203.60SiO2 was studied using impedance spectroscopy in the temperature range 380-925 deg C. In order to simulate the spectra obtained, simple equivalent circuits were used. At temperatures above a temperature, Tx, below which phase separation occurs, the specific conductivities determined can be fitted to the Arrhenius equation. Below Tx, deviations from Arrhenius behaviour are observed, which are due to the formation of an Na2O and B203 rich phase with larger specific conductivity and an SiO2 rich phase with lower specific conductivity.