以Al(NO3)3.9H2O、Si(OC2H5)4、ZrOCl2.8H2O和Ti(OC4H9)4为原料,用sol-gel法通过分步水解得到透明稳定性能好的复合溶胶,利用浸渍提拉方法在孔隙率为45%的-αAl2O3陶瓷基体表面涂覆凝胶膜经热处理得到陶瓷膜。采用XRD、FT-IR和SEM测试技术对膜的相组成、凝胶膜热处理中的变化和复合膜的微观形貌进行表征。结果表明,改变Ti组分的加入量,复合膜的主晶相将发生改变;提高热处理温度,胶体颗粒之间将生成更加稳定致密的氧桥键Si—O—Al和Ti—O—Al—O—Si等,从而提高薄膜的机械强度;适中的溶胶粘度是成膜的关键因素。

Research on Microstructures and Appearances of Al_2O_3-SiO_2-ZrO_2-TiO_2 Composite MembranesWU Jian-feng,ZHANG Xin,XU Xiao-hong,YANG Lan-fang,CHEN Jie,GUO Quan-sheng(Key Laboratory for Silicate Materials Science and Engineering of Ministry of Education,Wuhan University of Technology,Wuhan 430070,China)Al_2O_3-SiO_2-ZrO_2-TiO_2 composite sols which had well transparent and stability were prepared by sol-gel method through fractional hydrolyze used Al(NO_3)_3·9H_2O、Si(OC_2H_5)_4、ZrOCl_2·8H_2O and Ti(OC_4H_9)_4 as raw materials.Gels films were prepared on α-Al_2O_3 ceramic substrate surface with porosity 45% by dip-coating method,then ceramic membranes were gained through heat-treatment.XRD,FT-IR and SEM measuring and testing techniques had been used to analyse and characterize the phase composition,structure changes in heat-treatment process and microcosmic appearances.The study found out that change the addition of Ti sol,the composite membranes main crystal will be changed.Increased the heat-treatment temperature of gel membranes,the Si—O—Al and Ti—O—Al—O—Si bonds were formed between colloidal particles in order to improve mechanical intensity of the films;the sols viscosity was the key to form membranes.sol-gel route;four-component composite sols;structure;microstructure