热处理制度对LZAS玻璃陶瓷析晶和显微结构的影响

Effects of Heat-treatment on the Crystallization and Microstructure of Li_2O-ZnO-Al_2O_3-SiO_2 System Glass-ceramics

采用DSC、XRD、SEM等分析手段,研究了热处理制度对Li2O-ZnO-Al2O3-SiO2(LZAS)系玻璃陶瓷的析晶和显微结构的影响,并讨论了析晶机理。结果表明:610℃时开始析晶,晶体为纤微树枝状γⅡ-LZS;650℃时出现直径为0.5μm的球状方石英晶粒,随后晶粒消失;720℃时开始析出蜂窝状的β-石英固溶体,并且随着温度升高晶体逐渐长大;到850℃变为均匀的颗粒状β-锂辉石固溶体,大小为1μm左右。锂锌铝硅系玻璃陶瓷在热处理过程中会产生两种相变:γⅡ-LZS→γ0-LZS;方石英→β-石英固溶体→β-锂辉石固溶体。

The effects of heat treatment on the crystallization and microstructure of IZAS system glass- ceramic were studied by DSC, XRD and SEM, and the crystallization mechanism was also discussed. The results showed that the massive thin dendritic structure crystallization of γⅡ- LZS occurred after the glass was treated at 610 ℃ ; minor crystallization phase of spherical cristobalite formed at 650℃ with the diameter of 0.5 μm, and then it disappear; β-quartz solid solutions with the structure of honeycombshaped network occurred at 720 ℃, and the crystals increase gradually with crystallization temperature increasing; the even grain of β-spodumene solid solutions replaced E-quartz solid solutions when crystallization temperature was at 850 ℃, at the time the size of crystal particles was about 1 μm. There were two phases transition in the heat treatment process for the LZAS system glass ceramics：γⅡ-LZS→γ0-LZS, cristobalite→β-quartz solid solutions→β-spodumene solid solutions.