Effect of impurity in starting kaolin materials on sintering behavior of cordierite ceramics

摘要

Effect of impurities in kaolin materials on thesintering behavior of the cordierite ceramics was studied. Threekinds of kaolins were used, that is, Georgia kaolin, Chinesekaolin and New Zealand kaolin. Georgia kaolin without #alpha#-quartz and cristobalite only gave a dense sintered body. #alpha#-quartz contained in both Chinese kaolin and New Zealand kaolinwould retard the densification of sintered bodies. In the case ofChinese kaolin, chemical components except for MgO, A1_2O_3and SiO_2 in mixture accelerated the generation of liquid phaseat above 1300 deg C and apparent porosity in sintered bodydecreased by liquid phase sintering. In the case of New Zealandkaolin, cristobalite and #alpha#-cordierite crystallized at highertemperature than that of Georgia kaolin and Chinese kaolin.