Structural and acoustic properties of lead silicate glasses doped with alkali and alkaline earth oxides

Changes in the structure and acoustic properties of Na2O-K2O-CaO-PbO-SiO2 glasses related to the substitution of K2O by Na2O have been deduced. Many compositional parameters, such as mean atomic volume, packing density, the difference between density of the glass and its analogous crystalline structure, field strength of interstitial cations, number of network bonds per unit volume, average first-order stretching force constant, crosslink density and dissociation energy per unit volume have been evaluated using the known theoretical models. Correlations between acoustic and compositional properties yielded valuable information about the behaviour of the modifying oxides PbO, CaO, K2O and Na2O in the silicate network. Moreover, the validity of the Makishima \& Mackenzie theory has been verified for all the investigated glass samples. The results show that the theoretically calculated values of elastic moduli are in excellent agreement with the corresponding experimentally measured values.