关键词: 勃姆石(γ-AlOOH), 发泡剂(SDS), 氧化铝-莫来石, 发泡陶瓷

Abstract:

Alumina-mullite porous ceramics were prepared by foaming method using α-Al₂O₃ micropowder and SiO₂ micropowder as the raw materials,boehmite (γ-AlOOH) sol as the binder,and sodium dodecyl sulfate (SDS) as the foaming agent.Effects of boehmite sol addition (1%,2%,4%,5%,6% 8%,by mass) and SDS addition (1%,1.5%,2%,2.5%,3%,5%,by mass) on the apparent porosity and the crushing strength,and effects of the firing temperature (1 300,1 350,1 400,1 450,1 500,and 1 600 ℃) on the properties and the microstructure of the ceramics were researched.The results show that the apparent porosity of the ceramics decreases with boehmite sol addition increasing,but the crushing strength increases gradually.The apparent porosity increases first and then decreases with the increase of SDS addition,while the crushing strength show the opposite trend.The crushing strength increases first and then decreases with the firing temperature rising,but the apparent porosity decreases all the time.5% boehmite,2.5% SDS and 1 450 ℃ of the firing temperature are the optimal preparation condition,thus the crushing strength of 6.7 MPa,apparent porosity of 79.5%,and thermal conductivity of 0.087 W·(m·K)^-1 are obtained.

Key words: boehmite (γ-AlOOH), foaming agent (SDS), alumina-mullite, foam ceramics