炉料浸泡法制备低羟基含量锗酸盐玻璃

Low OH content germanate glass prepared by batch soaking process in CCl_4

以CCl4为除水剂,采用炉料浸泡处理工艺制备40GeO2-30SiO2-12Al2O3-6BaO-6CaO-6MgO光学玻璃,研究该工艺对锗酸盐玻璃的红外透过性能以及析晶行为的影响。结果表明,锗酸盐玻璃中OH吸收峰位于3338/cm(3.0μm)附近,通过Gauss分解将其分解为5个单峰并分别对其进行分析,认为锗酸盐玻璃中羟基振动频率的红移是由氢键强度变弱引起的。红外光谱分析表明,采用普通工艺制备的锗酸盐玻璃OH吸收系数为1.71/cm,而处理后玻璃OH吸收系数减少至0.25/cm。对样品的DTA与XRD分析表明,采用新工艺制备的玻璃中由于残留氯离子的存在,起到成核剂的作用,降低玻璃的析晶温度,提高玻璃的析晶速率。氯化物的引入使得玻璃中晶粒形貌由岛状转变为板状,提高玻璃的析晶程度。

40GeO2-30SiO2-12Al2O3-6BaO-6CaO-6MgO glass was prepared by using batch soaking process with CCl4 as dehydration agent. The influence of this process on the infrared transmittance and crystallization behavior of the germanium glass was investigated. The results show that the infrared spectra contains a single band at approximately 3 338/cm for the germanate glass. This broad absorption band is deconvoluted into five bands and some possible reasons for each band have been given. The absorption coefficient of hydroxyl in the germanate glass prepared by conventional melt quenching technique is 1.71 /cm while that of the one prepared by batch soaking process in CCl4 is 0.25/cm. The analyses of DTA and XRD indicate that the glass prepared by batch soaking process crystallizes at lower temperature and has bigger crystallization rate for the residual chlorine acting as a nucleation agent in the interspaces of the glass network structure. The SEM images show that the residual chlorine promotes the formation of crystallite and changes the shape of the crystallite cluster.