低温烧结法制备Al_(2)O_(3)多孔陶瓷及性能研究

Preparation and properties of porous Al_(2)O_(3) ceramics by low temperature sintering

为降低氧化铝粉体合成温度、缩短反应时间,采用低温燃烧法合成了氧化铝粉体,并将粉体进一步制备成多孔氧化铝陶瓷。具体实验过程为:将滤纸浸渍在Al^(3+)浓度不同的前驱体溶液中,在马弗炉中干燥和引燃滤纸;用H_(2)O_(2)溶液处理低温燃烧合成的粉体,再将制备的粉体压制成型后于不同温度下烧结。研究了溶液中Al^(3+)浓度和烧结温度对多孔氧化铝陶瓷的显气孔率、维氏硬度和气孔孔径的影响规律。实验结果表明:随溶液中Al^(3+)浓度的增加,多孔氧化铝陶瓷的显气孔率和吸水率增加,氧化铝晶粒尺寸略有增大,维氏硬度降低;随烧结温度的升高,多孔氧化铝陶瓷的吸水率、显气孔率和维氏硬度皆呈下降趋势。

In order to reduce the synthesis temperature and reaction time of alumina powders,we prepared alumina powders by combustion synthesis,which were subsequently used to fabricate porous alumina ceramics.The filter paper was immersed in solutions with different Al^(3+)concentrations,followed by drying and ignition on a muffle furnace.Then the synthesized powders were treated using H_(2)O_(2) solutions.The as-prepared powders were pressed into rectangular specimens and sintered at different temperatures.The effects of Al^(3+)concentrations in the solutions and sintering temperatures on the apparent porosity,Vickers hardness and pore diameters of porous alumina ceramics were studied.The results show that with the increase of Al^(3+)concentration in the solutions,the apparent porosity and water absorption of porous alumina ceramics increase,except that the alumina grain size increases slightly,while the Vickers hardness of porous alumina ceramics decreases.With the sintering temperature increasing,the water absorption,apparent porosity and Vickers hardness of porous alumina ceramics all show a downward trend.