【摘要】 以高纯纳米氧化铝为原料,以叔丁醇-水为溶剂,以共聚物Isobam为分散剂和交联剂,通过凝胶注模成型的方法制备了孔隙率为80%~85%的氧化铝纳米多孔陶瓷,并研究在最佳醇-水体积比(3:7)条件下,Isobam的浓度对料浆流变性和烧结试样孔隙率、力学性能及隔热性能的影响。结果表明:Isobam的浓度为0.8%时(质量分数),料浆的粘度最低、分散状态最稳定。成型后的坯体经1000?C/1h烧结后,所得到的试样孔隙率最高(>85%),孔径均匀分布在纳米尺度之内,热导率为0.06W·(m·K)-1,且经1350?C/1h烧结后,孔隙保留率仍为94.72%。更多还原

【Abstract】 Using high purity alumina powder as raw material, tertiary butanol-water mixture as solvent, copolymer Isobam as dispersant and cross-linking agent, nano-porous alumina ceramics with porosity ranged from 80% to 85% were fabricated by gel-casting process. The effect of Isobam concentration on rheological behavior of the slurries, the porosity, mechanical property and heat-insulating property of nano-porous alumina ceramics were investigated. The results show that the slurry with low viscosity and high stability can be prepared by adding 0.8wt % Isobam under the circumstance of optimum volume ratio of the solvent（VTBA:VH₂O=3:7）. The nano-pores alumina ceramics with the highest porosity（>85%） can be obtained after sintering the molding body at 1000 ℃ for 1 h. The sizes of the porous are uniformly distributed within nanoscale, the thermal conductivity of the ceramics is 0.06W·（m·K）^-1, and after sintering at 1350 ?C for 1 h, the porosity retention rate of the ceramics is 94.72%.更多还原