自蔓延高温合成(SHS)是制备多孔陶瓷的一种新兴方法。作者将传统制备方法中的发泡技术引入到SHS中,以Al并口TiO2为原料,并辅助以高温发泡剂,制备出了Al2O3-TiO-TiO2复相多孔陶瓷。使用SEM和XRD进行了分析表征。宏观和金相显微观察测得Al2O3-TiO—TiO2复相多孔陶瓷具有毫米级和微米级的孔梯度,用阿基米德法测得其显孔隙率为35%~50%。研究表明:添加适量的高温发泡剂可增大Al2O3-TiO—TiO2复相多孔陶瓷的显孔隙率,但剂量超过0.5(摩尔分数)后,显孔隙率的变化不大;添加SiO2能够提高Al2O3-TiO—TiO2复相多孔陶瓷抗压强度,但是却会降低其显孔隙率。
Multiphase porous A1203-TiO-TiO2 ceramic was prepared by self-propagating high-temperature synthesis (SHS) with the reaction of AL and TiO2, and then analyzed and characterized by XRD and SEM. Direct observation and metallographic microscope indicated that multiphase porous Al2O3-TiO-TiO2 ceramic had pores gradient at millimeter level and micron level. Archimedean method showed that the porosity was 35%~50%. Further investigation showed that porosity was increased by adding proper high temperature foaming agent, but little changed after the high temperature foaming agent content exceeded 0.5 (mole fraction). Compression strength could be increased by doping SiO2, but porosity would be decreased.