用Sol-Gel法制备氧化铝多孔陶瓷的研究

STUDY ON POROUS ALUMINA CERAMICS PREPARED BY Sol-Gel

主要研究了羟铝比（［ＯＨ－］／［Ａｌ３＋］）、铝离子浓度及成孔剂含量和温度对ｓｏｌ－ｇｅｌ法制备的氧化铝多孔陶瓷气孔率、气孔分布和显微结构的影响。实验结果表明：铝溶胶的最佳组成是羟铝比为２．３８，铝离子浓度为１０ｗｔ％，成孔剂含量为５ｗｔ％。随着烧成温度由１４２０℃升至１５００℃时，８＃试样的显微结构由松散的片状向连通贯穿的整体结构转变。在１４５０℃时，２＃试样（［ＯＨ］／［Ａｌ３＋］＝２．３３）主要是单个颗粒连接的结构；８＃试样（［ＯＨ］／［Ａｌ３＋］＝２．４０）主要是相互贯穿连成一体的结构。前者气孔率小于后者。

The influence of the ratio( / ), ,content of pore-forming material and calcinating temperature on the properties such as appearant porosity,PSD and microstructures of porous alumina ceramics was briefly studied.The experiments show that the optimal condition of alumina sol is /Al]=2.38, =10wt% and five percent by weight of pore-forming material for appearant porosity and bulk density.The microstructure of sample 8# is converted from loose and seperated pellets to crossing-linked structure with the increment of temperature.The microstructure of sample 2# is briefly comprised by aggregated particles,that of sample 8# by crossing-linked network.The former is lower and narrower than the latter in appearant porosity and PSD at 1450,respectively.