Elastic and thermal properties of lithium borate glass system

Elastic and thermal properties of lithium borate glasses xLi(2)O-(1-x)B2O3 (x=0(.)06-0(.)28) were investigated by means of Brillouin scattering spectroscopy and modulated differential scanning calorimetry WDSO. The temperature dependences of elastic modulus and absorption coefficient of lithium borate glasses were measuredfrom 25 to 600 degrees C. The glass system showed a stiffening tendency and a higher onset temperature of softening with increasing mole fraction of Li2O. We successfully observed the change in the elastic modulus at the glass transition temperature (T-g). The elastic parameters showed larger temperature dependences above T-g, while they change little below T-g. From MDSC measurement, T-g and the profile of heat capacity exhibited significant composition dependence. With increasing concentration of Li2O, T-g increased and the temperature range of Tg became narrower. These results might be due to the change in some amount of the crosslinking borate units from triangle BO3 to tetrahedral BO4. The Cole-Cole plot Of complex heat capacity was examined and wellfitted by Davidson-Colefunction. The parameter derived from the function was determined and P was 0(.)58 at x=0(.)18. This non-Debye nature is explained by the variation of intermediate range structures of borate glass.