Aging, glass transition, supercooled and equilibrium liquid states of alkali germanate glasses studied by Brillouin scattering

作者：Kaneda Kazuhiro; Arae Katsuhiko; Kodama Masao; Kojima Seiji^*

来源：Journal of Non-Crystalline Solids, 2012, 358(4): 799-803.

DOI：10.1016/j.jnoncrysol.2011.12.027

• Alkali germanate glass
• Glass transition temperature
• Elastic property
• Brillouin scattering
• Coordination number

The elastic properties of alkali germanate glasses, xR(2)O center dot(100 - x)GeO2 (R = Li, Na, K, Rb, Cs ; x = 14, 28), have been studied by Brillouin scattering in the wide temperature range up to 1200 degrees C. The remarkable aging effect of Brillouin shift Delta nu(L) has been observed below a glass transition temperature T-g approximate to 500 degrees C. The temperature dependence of longitudinal sound velocity V-L of well annealed glasses shows the gradual decrease below T-g, while on further heating the remarkable decrease is observed above T-g. The scaled temperature dependence of V-L is nearly independent on alkali metals below the melting temperature T-m. While on further heating above T-m, the drastic decrease of V-L and increase of alpha(L) show the remarkable alkali dependence. It may be attributed to the appearance of dynamic process related to ionic hopping of alkali metals released from glass network above T-m.

• 出版日期2012-2-15