Abstract
This paper presents a model to account for the electrical relaxation behaviour of glasses in which a vacancy mechanism prevails. The vacancies existing in glass a priori are constant in number and usually are in excess over those generated by thermal motion in the sense of Frenkel's defect theory. The pathways of vacancies form a net system with junctions and impasses. The displacement of vacancies in the impasses is deemed especially responsible for the relaxation process observed when a glass is subjected to an external electric field. According to the model (i) the dispersion of permittivity is inversely proportional to the temperature, and (ii) as the temperature is varied the curves of the ratios of the permittivity and dielectric loss, versus the dispersion, as a function of the logarithm of angular frequency, remain constant in shape. It follows from the model that a certain proportion of alkali ions in glass cannot be replaced either in an ion exchange process or by electrolysis if the temperature is not very high.
Published Version
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