Y_2O_3对高铝粉煤灰合成莫来石的影响  

Effect of Y_2O_3 on Synthesizing Mullite from High Alumina Fly-Ash

作　　者：邢净[1] 李金洪[1] 魏尊莉[1] 

机构地区：[1]中国地质大学材料科学与工程学院矿物材料国家专业实验室,北京100083

出　　处：《硅酸盐通报》2007年第2期291-295,315,共6页Bulletin of the Chinese Ceramic Society

基　　金：国家自然科学基金(40602008);矿物材料国家专业实验室开放基金资助项目(A05005)

摘　　要：研究了Y2O3和温度对高铝粉煤灰合成莫来石性能、结构、组成和微形貌的影响。结果表明:当到1500℃时,添加物质的量分数为5%Y2O3时,所得试样的显气孔率和吸水率最小,分别为0.53%和0.19%,抗折强度为128.3MPa,相应的莫来石含量达到80.8%;在1500℃的温度条件下,增加Y2O3,试样的抗折强度显著增加。SEM分析表明:Y2O3在低温(1100～1400℃)时促使莫来石形成网状结构,而较高温度(1500℃)时则有利于长柱状莫来石生长;升温过程中,方石英、刚玉相相继消失,莫来石相增加,莫来石经历了短柱状向长柱状生长的过程。In this paper,the influence of temperature and Y2O3 on the properties,crystal structure,mineral constitute and morphology of mullite materials using fly-ash as main raw materials was studied in detail.The experimental results indicate that the relative high-performed mullite materials were obtained when fired at 1500℃ and doped 5mol% Y2O3,with the porosity 0.53%,water absorption 0.19%,flexural strength 128.3MPa,mullite content 80.8%;the more Y2O3 was introduced,the higher flexural strength reaches when the higher flexural strength reaches when the temperature is 1500℃. SEM analysis results indicate that mullite mostly exist in the shape of reticular-like ball at lower temperature （1100-1400℃） while long rectangular parallelepiped at higher temperature （ 1500℃ ） under the condition of Y2O3, cristobalite and corundum vanished gradually and mullite phase increases as the temperature rising, and mullite shape undergoes the course from puncheon to long parallelepiped.

关 键 词：Y2O3 粉煤灰 莫来石 

分 类 号：TQ175.714[化学工程—硅酸盐工业]