Dielectric Losses of Some Simple Ternary Silicate Glasses

The effect on alkali ion mobility of compositional changes in simple glasses was investigated by observing the dielectric loss behavior in a number of ternary glass systems, formed by adding increasing amounts of various third components to potassia‐silica and soda‐silica base glasses. Oxides of barium, strontium, calcium, cadmium, lead, magnesium, zinc, aluminum, boron, tin, zirconium, titanium, and silicon were introduced. Tan δ values were determined at room temperature and at a frequency of 1 kc. per second. Na + ion mobility was found to be profoundly influenced by the type and amount of third component present. RO oxides decreased tan δ by amounts which appear to bear some relation to the size of the cation introduced. Tan δ curves for the MgO and ZnO series were unique in that each was characterized by a pronounced minimum and maximum. Curves for SnO 2 , Al 2 O 3 , and ZrO 2 additions passed through a minimum and in the latter two cases rose to tan δ values greater than that of the base glass itself. Curves for the series containing B 2 O 3 and TiO 2 continued to lower values throughout the range of compositions studied. The characteristic shapes of the loss curves are discussed with reference to the roles assumed by the introduced cations.