Ultrasonic, FTIR and thermal investigations of SiO_2-Na _2O-CaO-P_2O_5 glasses doped with CeO_2

摘要

The longitudinal and shear ultrasonic wave velocities for different compositions of SiO_2-Na_2O-CaO-P_2O_5 glasses were measured at room temperature (305 K) using a pulse-echo method at a frequency of 4 MHz. The elastic moduli, Poisson's ratio, microhardness, Debye temperature and other ultrasonic parameters were obtained from experimental data and analyzed using bond compression theory. By calculating the number of network bonds per unit volume, the average stretching constant, and the average ring size, information about the structure of the glass can be deduced. Structural changes after doping with CeO_2 were investigated by FTIR spectroscopy, and by measurements of the thermal expansion coefficient, glass transition and softening temperature to throw more light on the characterization of these glasses.