Interpretation of elastic properties and structure of TiO2-CaO-Al2O3-B2O3 glasses

Elastic moduli, Poisson's ratio, microhardness and Debye temperatures of the 30CaO.30Al 2 O 3 .40B 2 O 3 glasses doped with 5, 10, 15 and 20 mol% TiO 2 were obtained at room temperature using the pulse echo ultrasonic technique. The variation of these parameters with composition was interpreted quantitatively based on the bond compression and ring deformation models, to study the effect of TiO 2 on structure of these glasses. The theoretical bond compression bulk moduli and Poisson's ratios have been calculated for each glass sample. The connectivity and hence the acoustic properties of these glasses depend strongly upon TiO 2 concentration, the network becoming more rigid and compact with the addition of TiO 2 due the formation of TiO 6 , AlO 4 and BO 3 groups. A semi-empirical formula was presented to correlate the ultrasonic attenuation at room temperature on the one hand and the oxygen density and structural parameters on the other.