浸浆制备过程中陶瓷膜厚度控制及其模型化

在毛细过滤和薄膜形成机理的基础上，采用化学工程实验与模型化方法，对浸浆成型法制备多孔α-Al₂O₃陶瓷膜过程中，膜厚与影响因素之间的关系进行了理论分析和实验研究. 结果表明：膜厚受到制膜液粉体浓度、制膜液黏度、粉体粒径大小、载体纯水渗透性能以及涂膜过程中浸浆时间和载体提升速度等因素的影响. 通过膜厚与影响因素间的数学模拟，建立了膜厚控制模型. 并以ZrO₂粉体为原料，采用相同方法制备ZrO₂陶瓷膜对模型进行了验证，模拟计算值与实测值基本一致.

Modeling and control of ceramic membrane thickness during dip-coating process

α-Al₂O₃ membrane supported on α-Al₂O₃ porous substrate was formed by dip-coating and the formation process of the top layer was investigated based on experiments and theories of capillary filtration and film-coating. A model was developed to interpret quantitatively the formation process of the top layers on the porous substrate and all variables affecting top layer thickness were considered in the model.The results of theoretical analysis showed that the effects of six variables,namely the mass concentration of ceramic powder(W_s), the viscosity of suspension (η), the diameter of ceramic powder(r), the pure water permeability of support(Q),dipping time(t) and the withdrawal speed of the support(U),on the thickness of the top layer were highly significant. In order to validate the model developed,ZrO₂ membranes were prepared by dip-coating using the slurry with different mass concentrations of ZrO₂ powder. The experimental data of the thickness of the as-prepared ZrO₂ membranes showed good agreement with the model.