ZrO2/Al2O3复相泡沫陶瓷过滤器制备工艺研究

采用有机泡沫浸渍法制备泡沫陶瓷,研究了各种不同工艺因素对泡沫陶瓷性能的影响。采用XRD、SEM对泡沫陶瓷的相组成及微观结构作了分析与探讨。结果表明,在粘结剂聚乙烯醇加入量为0.5%,减水剂木质素磺酸钙加入量为0.5%,流变剂苏州土加入量为1.5%时,调整分散剂的加入量,当浆料中分散剂四甲基氢氧化铵的质量分数为0.9%时,可获得具有较佳分散性能的浆料。浆料的固相含量为85%时最适合挂浆的需求。对氧化锆氧化铝复合浆料进行进一步分析表明,氧化铝的加入量为20%时,浆料具有较小的粘度。烧结体的XRD分析表明,氧化铝加入量为20%时较好地抑制了t-ZrO2→m-ZrO2转变的发生,将大量的能发挥应力诱导相变的亚稳态四方相氧化锆保留了下来,从而提高了烧结体的力学性能。SEM分析也表明加入适量的氧化铝可有效抑制氧化锆晶粒的长大,并且起到颗粒弥散增强的作用。

Study on the Preparation Technics of ZrO2/Al2O3 Multiphase Foam Ceramic

The foam ceramics were prepared by impregnation a polyurethane sponge with ceramic slurry in the present studies. The effects of different technological parameters on properties of foam ceramics were studied. The phase and microstructure of foam ceramics were analyzed by XRD and SEM methods. The experimental results show that when the low temperature adhesive polyvinyl alcohol is 0.5%, the high temperature adhesive silicasol is 0.5%, water reducing agent calcium lignosulphonate is 0.5%, rheologic agent Suzhou clay is 1.5%, the best dispersive slurry can be obtained by adding 0.9 weight percent of TMAH. The slurry with 85 weight percent of ceramic powders is best for the need of dipping. When the powder consisted of 20% weight per cent Al2O3 and 80% weight per cent ZrO2, the slurry has the low viscosity. The XRD results of the sintering bodies indicated that the transition of t-ZrO2 to m-ZrO2 was inhibited by the introduction of Al2O3, which was in favor of leaving large amount of metastable state tetragonal ZrO2 in the body and resulted in higher mechanical properties of the sintering bodies. The best content of the Al2O3 is 20%. The SEM analysis shows that the Al2O3 particles disperse in the matrix which can inhibit the grain growth of ZrO2 and toughening the materials.