ELECTRICAL PROPERTIES AND INTERNAL FRICTION IN IRON PHOSPHATE GLASSES.

The internal friction and electrical properties of glasses in 40 Fe//2O//3 multiplied by (times) 60 P//2O//5 system were measured. The quantitative values of dynamic modulus G prime and dynamic loss G double prime on internal friction were obtained by considering the shape factor. G prime was 3. 0 multiplied by 10**9-1. 0 multiplied by 10**1**0 dyn/cm**2, and G double prime was 1. 0 multiplied by 10**7-5. 0 multiplied by 10**7 dyn/cm**2 in the range of valence ratio (R//e equals Fe**2** plus /Fe**2** plus plus Fe**3** plus ) R//e equals 0. 13 to R//e equals 0. 37. The two peaks were observed in the temperature range from minus 100 degree to 400 degree C at a frequency of about 1 Hz. The area of the low temperature peak (at about 0 degree C) increased with increasing valence ratio R//e similar to that in the D. C. conductivity and dielectric increment. All of internal friction peak and electrical properties showed maxima at R//e equals 0. 5. Frequency temperature dependence of the dielectric loss peak and low temperature peak on internal friction showed a straight line and its activation energy was 0. 55 ev. The internal friction peak in glasses of 40 MgO multiplied by (times) 60 P//2O//5 system was not observed in the temperature range minus 100 degree to 200 degree C. From the above results the peak observed at low temperature was due to the hopping of localized electron in small polaron. On the other hand, the activation energy of high temperature peak was about 1. 6 ev (37 kcal/mol) and the high temperature peak decreased with increasing R//e ratio. Consequently, the peak observed at high temperature was considered as due to the interaction between proton and non-bridging oxygen ions.