Phosphate-based glasses: Prediction of acoustical properties

In this work, a comprehensive study has been carried out to predict the composition dependence of bulk modulus and ultrasonic attenuation coefficient in the phosphate-based glass systems PbO-P₂O₅, Li₂O-TeO₂-B₂O₃-P₂O₅, TiO₂-Na₂O-CaO-P₂O₅ and Cr₂O₃-doped Na₂O-ZnO-P₂O₅ at room temperature. The prediction is based on (i) Makishima-Mackenzie theory, which correlates the bulk modulus with packing density and dissociation energy per unit volume, and (ii) Our recently presented semi-empirical formulas, which correlate the ultrasonic attenuation coefficient with the oxygen density, mean atomic ring size, first-order stretching force constant and experimental bulk modulus. Results revealed that our recently presented semi-empirical formulas can be applied successfully to predict changes of ultrasonic attenuation coefficient in binary PbO-P₂O₅ glasses at 10 MHz frequency and in quaternary Li₂O-TeO₂-B₂O₃-P₂O₅, TiO₂-Na₂O-CaO-P₂O₅ and Cr₂O₃-Na₂O-ZnO-P₂O₅ glasses at 5 MHz frequency. Also, Makishima-Mackenzie theory appears to be valid for the studied glasses if the effect of the basic structural units that present in the glass network is taken into account.