【作者】 张芳；

【导师】 徐晓虹；

【作者基本信息】 武汉理工大学 ， 材料学， 2002， 硕士

【摘要】 本文研究了利用新开发的具有特殊物化工艺性能的累托石为粘土原料，添加滑石、工业氧化铝，采用添加造孔剂压制成型及前驱体浸渍成型两种方法制备多孔陶瓷。采用KZL-30型电动抗折仪、JVC读数显微镜、SX-40型扫描电镜、D／MAX-Ⅲ型X射线衍射仪等测试了样品的理化性能及微观结构。结果表明，样品的显气孔率为28．53～49.21％，吸水率为15．36~36．26％，体积密度为1.36~1．86g／cm3，抗折强度为12．2~22．3Mpa，热膨胀系数为2．95×10(-6)／℃，耐火度为1390℃，气孔呈7~180μm的梯度变化，抗热震性优良。同时将累托石质配方与高岭土质配方所制得的多孔陶瓷进行了比较研究。 通过研究得出以下结论：①以累托石、滑石和Al2O3为原料，以煤粉为成孔剂，采用压制成型法通过调整骨料粒径及成孔剂粒径的相互复合，在1220℃下可制得具有呈连续变化的孔梯度分布多孔陶瓷，且随着成孔剂含量的提高，显气孔率增加，强度和体积密度均降低。②将不同孔径的聚氨酯泡沫前驱体分别浸渍泥浆，再以一定的方法将其叠放在一起经过干燥、烧成等工艺可以制得具有一定强度的孔梯度多孔陶瓷。③在相同条件下，以累托石质配方制备的样品的抗折强度、体积密度大于以高岭土质配方制备的样品。④累托石质配方样品中的堇青石相含量多于高岭土质配方的样品中的。⑤累托石质配方的样品的热膨胀系数比高岭土质配方的样品的小，而耐热震性能比高岭土质配方的样品的高。⑥在压制成型过程中，累托石质坯料，不需要添加粘结剂就可以压制出强度较高的坯体，而高岭土质坯料，必须添加 7～8％的粘结剂才能压制出具有一定强度的坯体。⑦采用浸渍前驱体法成型时，累托石质配方的料浆含水率为54～60％，泥浆比重为1．282~1．360；高岭土质配方的料浆含水率为45%，泥浆比重为1．495。⑧采用浸渍前驱体法制得的样品，孔的均匀性优于压制成型的样品。⑨压制成型法制备工艺的关键技术是造粒和混料，而浸渍法成型工艺的关键是泥浆比重的调制和浸渍。更多还原

【Abstract】 Porous ceramics were prepared by two methods using rectorite ,a new developed clay with special physical and chemical properties ,one is that pore-forming material was added to raw materials and formed by pressing ,the other is the organic precursor dip forming process . The physical and chemical properties and microstructures of product have been tested by KZL-30 type electric bending strength tester,JVC reading microscope,SX-40 SEM and D/MAX XRD. The results show that apparent porosity is 28.53-49.21%,water adsorption is 15.36-36.26%,bulk density is 1.36-1.86%,bending strength is 12.20-22.3MPa,the coefficient of. thermal expansion is 2.95 X 10-6 at 20-750 ,refractoriness is 1390,gradient pore of sample range from 7 n m to 180 Mm,thermal shock resistance is good. In addition,the results compared with that of porous ceramics made of kaolinite.The conclusions were below through this study:Gradient porous ceramics with continuous pore size used raw material of retorite(or kaolinite),talc and alumina were prepared by compounding different size of grain and pore-forming materials at 1220,product adopted coal powder as pore-forming materials,with increasing pore-forming materials,the apparent porosity was increased too,whereas strength and bulk density were decreased.(2)Polyurethane organic precursors with different pore siize were dipped in slip,then super posited them together and the gradient porous ceramics were made by drying and firing.(3)At the same condition,the bending strength and bulk density of sample made of retotite were better than that of sample of kaolinite.Cordierite in rectorite sample is much than that in kaolinite sample.(5)Thermal expansion coefficient of rectotite sample was lower than that of kaolinite sample,but thermal shock resistance of rectotite sample was better than that of kaolinite sample.Body with made of retotite could be pressed with no additive,had a certain strength. If it wanted a certain strength using material of kaolinite ,it must added 7%-8% additive.When it was pressed by dipping organic precursors ,containing water rate of the sample made of rectorite was 54-60%,proportion of slurry was 1.282-1.360 ,whereas containing water rate of the sample made of kaolinite was 45%,proportion of slurry was 1.495.Homogeneity of pore of sample by dipping was better than that of sample by pressing.A key technology in pression was made particles and mixed materials,but in dipping method,adjusting slip proportion was a important step.更多还原