Effect of Doping by Different Transition Metals on the Acoustical Properties of Alkali Borate Glasses

Longitudinal and shear ultrasonic wave velocities were measured in binary Li(2)O-2B(2)O(3) glasses doped with different transition metal oxides (TMOs) (where TMO = V(2)O(5), Fe(2)O(3), Cr(2)O(3), NiO, TiO(2), MnO(2) and CuO) using pulse echo technique. Measurements were carried out at 4 MHz frequency and at room temperature. Elastic moduli and some other physical parameters such as acoustic impedance, Debye temperature, thermal expansion coefficient, and latent heat of melting were calculated. Results indicated that these parameters depend upon the TMO modifier i.e., the ionic radius of the transition metal cation. Quantitative analysis has been carried out, in order to obtain more information about the structure of these glasses, based on bond compression model, and the Makishima and Mackenzie model, i.e., the cation-anion bond of each TMO.