Eleventh International Conference on Internal Friction and Ultrasonic Attenuation in Solids
J. Phys. IV France 06 (1996) C8-671-C8-674
Internal Friction of (SiO2)1-x (GeO2)x GlassesT. Kosugi1, H. Kobayashi2 and Y. Kogure3
1 Department of Physics, Hiroshima University, Higashi-Hiroshima 739, Japan
2 National Research Laboratory of Metrology, Tsukuba 305, Japan
3 Teikyo University of Science & Technology, Uenohara, Yamanashi 409-01, Japan
Internal friction of (SiO2)1-x (GeO2)x glasses (x = 0, 5, 10, 24 and 100 mole%) is measured at temperatures between 1.6 and 280 K. The data are filted with the equations for thermally activated relaxation with distributing activation energies in symmetrical double-well potentials. From the determined relaxation strength spectra for each sample, the contributions from each type of microscopic structural units are calculated assuming that transverse motion of the bridging O atom in Si-O-Si, Si-O-Ge or Ge-O-Ge bridge (T model) is the microscopic unit responsible for relaxation. For instance, the magnitude of internal friction for SiO2-5% GeO2 or 24% GeO2 is calculated from the data of pure SiO2, SiO2-10% GeO2 and pure GeO2. The calculated results agree well with the measurements of SiO2-5% GeO2 and SiO2-24% GeO2. Thus T model is shown to be quantitalively consistent with internal friction of SiO2-GeO2 binary glasses.
© EDP Sciences 1996