标题：Fabrication and properties of porous mullite ceramics from calcined carbonaceous kaolin and alpha-Al2O3
作者机构：[Bai, JH]Shandong Univ Technol, Sch Mat Sci & Engn, Zibo 255049, Shandong, Peoples R China.
通讯作者地址：[Bai, JH]Shandong Univ Technol, Sch Mat Sci & Engn, 12 Zhangzhou Rd, Zibo 255049, Shandong, Peoples R China.
关键词：Mullite; Porous ceramics; Carbonaceous kaolin; Fracture behavior
摘要：High purity calcined carbonaceous kaolin and alpha-Al2O3 powders were employed to prepare porous mullite ceramics (Sample A) using graphite as pore former with the reaction sintering method. For the purpose of comparison, porous mullite ceramics (Sample B) was also fabricated from the uncalcined carbonaceous clay incorporated with alpha-Al2O3 powders. Mullitization in the two samples was both nearly complete at 1500 degrees C, despite the fact that calcination of the clay remarkably depressed mullitization and promoted the formation of glass phase. The Sample A sintered at 1500 degrees C fractured mainly in an intergranular way, while the Sample B mainly underwent transgranular fracture. The experimental results revealed that densification behavior/open porosity of the Sample A was far more sensitive to sintering temperature. The pore size of the Sample A as well as the Sample B sintered at 1500 degrees C was in a narrower range of 0.3-5 mu m. (C) 2009 Elsevier Ltd and Techna Group S.r.l. All rights reserved.