摘要
用传统熔体冷却法制备了氧化锆质量含量为0.0—10.0%的CaO-BaO-Y2O3-Al2O3-SiO2-GeO2玻璃。采用DSC、XRD、SEM等分析测试方法研究了氧化锆含量对锗酸盐玻璃的析晶行为与显微结构的影响。研究表明,氧化锆能显著影响锗酸盐玻璃的析晶行为,当玻璃中氧化锆质量含量少于6.0%时,玻璃的晶化受表面析晶机制所支配,表面晶化层中晶体为Ge2Al6O13与Y2Ge2O7,增加成核剂含量能够弱化表面析晶,使玻璃向整体析晶转化。随氧化锆含量增加,表面晶化层与内层未晶化玻璃界面处的晶体由无序生长变为垂直界面生长,并从板条状向枝晶发展。当成核剂质量含量为6.0%时,玻璃中同时出现表面析晶与整体析晶现象,进一步增加成核剂氧化锆含量时,玻璃完全表现为整体析晶,其晶体为Ge2Al6O13,Y2Ge2O7及ZrO2。
CaO-BaO-Y2O3-Al2O3-SiO2-GeO2 glasses with ZrO2 contents from 0.0 to 10.0 % were prepared by conventional melt quenching technique. Differential scanning calorimeter, X-ray diffraction and scanning electron microscopy were used to study the effect of nucleating agent ZrO2 on crystallization behavior and microstructures of the glass system. The results show that when ZrO2 content is lower than about 6.0 %, the forming of the crystals in the glass-ceramics is controlled by surface crystallization mechanism. The crystalline phases on the surface layer are Ge2Al6O13 and Y2Ge2OT. Increasing ZrO2 content weakens the surface crystallization and causes it converting to bulk crystallization. The crystals on the boundary between the surface crystallization layer and the inner glass grow perpendicular to the boundary from disorderly by introducing ZrO2, and the crystal growth shows a change from strip shape arrangement to arborescent development. The surface crystallization arid bulk crystallization co-exist in the glass when the content of ZrO2 is 6.0 %. Further increasing ZrO2, the bulk crystallization predominates in the glass-ceramic and the crystalline phases are Ge2Al6O13, Y2Ge2OT, and ZrO2.
出处
《武汉理工大学学报》
CAS
CSCD
北大核心
2009年第4期87-91,共5页
Journal of Wuhan University of Technology
基金
国家民口配套项目(JPPT-115-332)
关键词
锗酸盐玻璃
微晶玻璃
ZRO2
析晶行为
germanate glass
glass-ceramies
ZrO2 nucleating agent
crystallization behavior
