摘要
In this work, a new TeO2-BaO-BaF2-La2O3-LaF3 oxyfluorotellurite glass system is investigated. Differential thermal analysis (DTA) and structural analysis by Raman scattering spectra are reported on the glasses. The DTA results indicated that an increase of fluoride content in the glasses decreases the glass transition temperature (Tg) and increases the crystallization onset temperature (Tx). As a result the 70TeO2·20BaF2·10LaF3 glass showed a large Hruby's parameter, possessing excellent thermal stability. Changes in glass network structure with fluoride content are discussed based on the Raman scattering spectra of glasses. The glass network structures in the 70TeO2·4(20-x)BaO·xBaF2·(10-y)La2O3·yaF3 glasses are basically composed of both Te(O, F)4 and Te(O, F)3 units, but the Te(O, F)4/Te(O, F)3 ratio in the glass becomes higher with increasing fluoride content. This may be considered one of the reasons why the 70TeO2·20BaF2·10LaF3 glass exhibits excellent thermal stability.
In this work, a new TeO2-BaO-BaF2-La2O3-LaF3 oxyfluorotellurite glass system is investigated. Differential thermal analysis (DTA) and structural analysis by Raman scattering spectra are reported on the glasses. The DTA results indicated that an increase of fluoride content in the glasses decreases the glass transition temperature (Tg) and increases the crystallization onset temperature (Tx). As a result the 70TeO2·20BaF2·10LaF3 glass showed a large Hruby's parameter, possessing excellent thermal stability. Changes in glass network structure with fluoride content are discussed based on the Raman scattering spectra of glasses. The glass network structures in the 70TeO2·4(20-x)BaO·xBaF2·(10-y)La2O3·yaF3 glasses are basically composed of both Te(O, F)4 and Te(O, F)3 units, but the Te(O, F)4/Te(O, F)3 ratio in the glass becomes higher with increasing fluoride content. This may be considered one of the reasons why the 70TeO2·20BaF2·10LaF3 glass exhibits excellent thermal stability.
基金
This work was supported by the National Natural Science Foundation of China under grant No.60207006
the Optical Science and Technology of Shanghai under grant No.022261046
"Qiningxing”Projert(No.04QMX1448)of Shanghai Municipal Science and Technology Conmission.
