Effect of rare earth (Pr 2O 3, Nd 2O 3, Sm 2O 3, Eu 2O 3, Gd 2O 3 and Er 2O 3 ) on the acoustic properties of glass belonging to bismuth–borate system

Abstract

Bismuth–borate glasses doped with some rare earth ions were studied with respect to the density, molar volume and the elastic moduli, Poisson’s ratio, Debye temperature, microhardness, softening temperature, acoustic impedance, diffusion constant and latent heat of melting. Ultrasonic velocities were measured by the pulse echo overlap technique at a frequency of 10 MHz and at room temperature. From these velocities and density values, various elastic moduli were calculated. The correlation of elastic stiffness, the cross link density, and the fractal bond connectivity of these glasses are discussed. The derived experimental values of shear modulus, bulk modulus, Young’s modulus, and Poisson’s ratio for our glasses are compared with the theoretically calculated values in terms of the bond compression model and Makishima–Mackenize theory.