Mechanical Properties and Structure of Heavy Metal Germanate and Silicate Glasses

Brillouin scattering spectroscopy has been used to evaluate the mechanical properties of glasses based on GeO sub 2 and SiO sub 2 combined with Bi sub 2 O sub 3, PbO, Sb sub 2 O sub 3, and Tl sub 2 O. Young's modulus E, shear modulus G, bulk modulus, isothermal compressibility, and Poisson's ratio were calculated. Relative to GeO sub 2, the more important mechanical properties, E and G, are generally enhanced by Bi sub 2 O sub 3 or PbO but degraded by Tl sub 2 O and Sb sub 2 O sub 3 additions. In the 3OBiO sub 1.5.3OPbO.XGeO sub 2. (4O-X)SiO sub 2 system, these properties are strongly enhanced for X=40 relative to GeO sub 2 and only weakly degraded for X=O relative to SiO sub 2. The observed changes are interpreted in terms of glass structure. The Raman scattering characteristics of these glasses have previously been reported: A.E. Miller et al., J. Non-Cryst. Solids 99, 289- 307 (1988). Potential use in fiber-optical amplifiers based on stimulated Raman scattering requires good mechanical properties.