添加GeO2對Li2O-Al2O3-SiO2 玻璃陶瓷的結晶、熱膨脹性及透光率的影響

Effects of GeO2 Addition On the Crystallization , Thermal Expansion, and Optical Transparency of Li2O-Al2O3-SiO2 Glass-Ceramics

盧俊元(Chun-Yuan Lue)

指導教授 ： 徐錦志

大同大學/工程學院/材料工程學系所/碩士(2005年)

摘要

含有奈米尺寸的high quartz固溶體晶體的 Li2O-Al2O3-SiO2 玻璃陶瓷具有透光及低熱膨脹之特性。本研究以商業量產之Zerodur®玻璃陶瓷成分為基礎，添加GeO2部分取代SiO2，期望能降低起始玻璃的黏度以利於成型加工，以及延長玻璃陶瓷的紅外光穿透截斷波長，增加光學應用範圍。研究結果顯示，GeO2含量增加，玻璃黏度下降。可經結晶化熱處理在玻璃基地中產生h-quartz 固溶體單一結晶相。相同熱處理條件下，GeO2含量增加時，晶粒徑增大。故影響玻璃陶瓷的可見光之穿透性。雖然可得良好穿透性的熱處理條件範圍變窄，但依然可以得到如未添加GeO2玻璃陶瓷之穿透率。含GeO2之玻璃陶瓷之熱膨脹係數隨著GeO2含量增加而上升。加入GeO2對起始玻璃或是玻璃陶瓷之紅外光穿透率及紅外光穿透截斷波長，並無影響。

關鍵字

黏度 ； 熱膨脹 ； 光學穿透率

並列摘要

Li2O-Al2O3-SiO2 glass-ceramics containing nano-sized h-quartz s.s. crystals have optical transparency and ultra-low thermal-expansion coefficient. The objective of the thesis is to explore the effect of GeO2 addition on the crystallization and properties of Li2O-Al2O3-SiO2 glass-ceramics. It is expected that the viscosity of the parent glass will be reduced to profit glass shaping, and the IR transmission cut-off will be shifted to longer wavelength.
The experimental results indicated that viscosity of glass reduced with the increase in GeO2 content. A single h-quartz s.s. phase can be formed in the parent glass subjected to nucleation and crystallization thermal treatment. The crystal size increased with the increasing GeO2 content, affecting the optical transmission in visible region for the glass ceramics. Although the conditions of thermal treatment to gain good transmission (70%) is more narrow with the increase in GeO2 content, materials with the transmission closed to Zerodur® can still be obtained. The coefficient of thermal expansion of glasses and glass-ceramics that contain GeO2 was increased with respect to the GeO2 free composition. Addition of GeO2 is useless on extending the IR transmission cut-off wavelength for glasses and glass-ceramics.

並列關鍵字

expansion ； h-quartz s.s. ； viscosity

參考文獻

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