CaO-BaO-Al_2O_3红外玻璃的形成及制备

Glass-forming ability and preparation on CaO-BaO-Al_2O_3 glasses

通过添加BaO增加了铝酸钙玻璃的成玻能力,确定了CaO-BaO-Al2O3三元系统的成玻区域:25～45 mol%的Al2O3,45～65mol%的CaO,0～18 mol%的BaO,在成玻区域内采用Hruby值研究Al2O3/CaO值和BaO含量对系统成玻能力的影响,发现当Al2O3/CaO值为0.60、BaO含量为8 mol%时,系统的成玻能力最强。以成玻能力最好的56CaO-8BaO-36Al2O3组成为基础,将真空烧结后几乎不含"水"的玻璃配合料分别在大气环境下、干燥氮气保护以及干燥氮气保护+CCl4搅拌等3种不同的条件下进行熔制,分析玻璃的红外透过光谱和残余水分含量。结果表明:采用干燥氮气保护+CCl4搅拌的方法,7mm玻璃在2.9μm的透过率接近84%,残余水分含量仅为0.0037,基本消除了OH-1的影响。

Glass-forming ability of calcium aluminate glasses is improved with the actlition of BaO, glass- forming region of CaO-BaO-Al2O3 ternary system is identified which is the area with content of Al2O3 between 25 mol% and 45 mol%, CaO between 45 mol% and 65 mol% and BaO between 0 mol% and 18 mol%. According to the study of ifrcdo, value. Influences of the ratio of content of Al2O3 and CaO（A/C） and the content of BaO on glass-forming ability were discussed based on the value of Hmby. It was found that glass-forming ability of 56 CaO-8 BaO-36 Al2O3 is best when the value of A/C is 0.60 and the content of BaO is 8 mol%. Batches without any water sintered in normal air inthe cicwstance, protected by dry nitrogen as well as stirred with COl4 respectivelf into, 30 as to detect as IR-transmittance spectrum and investigated by residual contents of water namely B（OH）. which indicated that the transmittance at 2.9 μm is nearly 84% and the residual B（OH） is 0.003 7. It was demonstrated that hydroxyl was almost removed by stirring with CCI4 while protected by dry nitrogen.