Li2S-B2O3硫氧化物体系玻璃晶化研究
STUDY ON THE CRYSTALLIZATION OF Li2S-B2O3SYSTEM GLASS
作者姓名：谢贤宁 导师姓名：高海春 导师职称：研究员
摘要: 本文利用高温熔融反应及液氮淬冷法制备了x Li2S-(1-x)B2O3玻璃。采用DTA、DSC、XRD、IR、Raman光谱等方法研究了玻璃的稳定性、基团结构、晶化行为及晶化产物相关系，得到如下主要结果与结论：
1．x Li2S-(1-x)B2O3体系的玻璃形成范围为：x≤0.45。该体系玻璃在x=0.25组成附近最为稳定。随Li2S含量增加，玻璃中的三配位硼转变为四配位硼并在x>0.25时形成了非桥氧和非桥硫键。玻璃结构经历了由平面网络转变为三维网络，最终离解为孤立小基团的变化过程。
2．玻璃的宏观状态对晶化过程特征温度及相状态均在影响。300℃以下温区为玻璃相对稳定区，300-450℃为玻璃的低温易晶化区，Tg以上温区为快速晶化区。采用量热法计算得到下班的等温与非等温晶化动力学参数。玻璃的晶化主要为表面晶化机制，晶化活化能E在80-150目粒度范围有最大值。晶化热-ΔH与峰值温度TP满足线性关系。
3．得到了五种不同组成的晶化产物并提供了它们的X射线粉末衍射数据，采用升温曲线法和静态平衡法研究了各组成玻璃的晶化与相变规律，建立了Li2S-B2O3体系晶态化合物之间的相关系。
关键词：玻璃；晶化与相变，晶化动力学；玻璃稳定性；Li2S-B2O3二元系相图 Abstract:x Li2S-(1-x)B2O3 system glasses have been prepared by fast cooling technique with liquid nitrogen.The glass stability,unit structure,crystallization behavior and phase relationship of crystallization products in this system are studied using DTA,DSC,XRD,IR,Raman methods.The following conclusions can be deduced from experimential results:
1.The glass formation region in x Li2S-(1-x)B2O3 system is x≤0.45.The most stable glass composition lies in the vicinity of 0.25 Li2S-0.75B2O3.With the addition of Li2S content,the glass structure changes gradually from plane network to three dimentional network,and last disassociates to isolated units.
2.Bulk and powdered samples have different influence on TC,TP and phase state in the crystallization process with a surface nu7cleation mechanism.The glasses are relatively stable below 300℃,and prone to crystallization between 300-450℃,and easy to be crystallized above Tg.In the partical size region of 80-150 mesh,the value of activation energy E is relatively higher.There is a linear relationship between crystallization enthalpy –ΔH and peak temperature TP.
3.Five different crystallization products are obtained,and their X-ray powder defrection data are provided.Furthermore,phase relationship of the above compounds in x Li2S-(1-x)B2O3 system is built up.
Key words: Li2S-B2O3 glass;Crystallization and phase transition;Crysallization kinetics;Glass stability; Li2S-B2O3 binary system;Phase diagram
Li2S-B2O3硫氧化物体系玻璃晶化研究
STUDY ON THE CRYSTALLIZATION OF Li2S-B2O3SYSTEM GLASS
作者姓名：谢贤宁 导师姓名：高海春 导师职称：研究员
摘要: 本文利用高温熔融反应及液氮淬冷法制备了x Li2S-(1-x)B2O3玻璃。采用DTA、DSC、XRD、IR、Raman光谱等方法研究了玻璃的稳定性、基团结构、晶化行为及晶化产物相关系，得到如下主要结果与结论：
1．x Li2S-(1-x)B2O3体系的玻璃形成范围为：x≤0.45。该体系玻璃在x=0.25组成附近最为稳定。随Li2S含量增加，玻璃中的三配位硼转变为四配位硼并在x>0.25时形成了非桥氧和非桥硫键。玻璃结构经历了由平面网络转变为三维网络，最终离解为孤立小基团的变化过程。
2．玻璃的宏观状态对晶化过程特征温度及相状态均在影响。300℃以下温区为玻璃相对稳定区，300-450℃为玻璃的低温易晶化区，Tg以上温区为快速晶化区。采用量热法计算得到下班的等温与非等温晶化动力学参数。玻璃的晶化主要为表面晶化机制，晶化活化能E在80-150目粒度范围有最大值。晶化热-ΔH与峰值温度TP满足线性关系。
3．得到了五种不同组成的晶化产物并提供了它们的X射线粉末衍射数据，采用升温曲线法和静态平衡法研究了各组成玻璃的晶化与相变规律，建立了Li2S-B2O3体系晶态化合物之间的相关系。
关键词：玻璃；晶化与相变，晶化动力学；玻璃稳定性；Li2S-B2O3二元系相图 Abstract:x Li2S-(1-x)B2O3 system glasses have been prepared by fast cooling technique with liquid nitrogen.The glass stability,unit structure,crystallization behavior and phase relationship of crystallization products in this system are studied using DTA,DSC,XRD,IR,Raman methods.The following conclusions can be deduced from experimential results:
1.The glass formation region in x Li2S-(1-x)B2O3 system is x≤0.45.The most stable glass composition lies in the vicinity of 0.25 Li2S-0.75B2O3.With the addition of Li2S content,the glass structure changes gradually from plane network to three dimentional network,and last disassociates to isolated units.
2.Bulk and powdered samples have different influence on TC,TP and phase state in the crystallization process with a surface nu7cleation mechanism.The glasses are relatively stable below 300℃,and prone to crystallization between 300-450℃,and easy to be crystallized above Tg.In the partical size region of 80-150 mesh,the value of activation energy E is relatively higher.There is a linear relationship between crystallization enthalpy –ΔH and peak temperature TP.
3.Five different crystallization products are obtained,and their X-ray powder defrection data are provided.Furthermore,phase relationship of the above compounds in x Li2S-(1-x)B2O3 system is built up.
Key words: Li2S-B2O3 glass;Crystallization and phase transition;Crysallization kinetics;Glass stability; Li2S-B2O3 binary system;Phase diagram