摘要
采用菱镁矿风化石、叶腊石、二氧化硅微粉为主要原料,研究分析烧成温度对合成堇青石结晶度、晶粒尺寸、晶相组成和显微结构来确定适宜的合成温度。用X′Pert plus软件对X射线衍射图进行拟合,分析试样的结晶度,用半定量(semi-quantification)法对试样结晶相中晶相组成进行计算,用Scherrer公式计算试样中堇青石、方石英晶粒的粒径大小。结果表明:采用菱镁矿风化石与叶腊石为原料合成堇青石,当温度由1350℃增加到1400℃,试样的结晶度增加,堇青石晶粒尺寸和堇青石相量增加,在1400℃时,试样结晶度最高,晶粒尺寸最大。晶相组成中堇青石相占67%,方石英相占33%。当温度大于1400℃,试样结晶度降低,堇青石和方石英晶粒尺寸减小,当温度在1500℃时,堇青石相消失,促进了方石英相析出。采用菱镁矿风化石与叶腊石为原料合成堇青石的最佳烧成温度为1400℃。
Cordierite was synthesized using decomposed magnesite,pyrophyllite and SiO2 power as raw materials.The effect of calcination temperature was studied on crystalinity,grain size,microstructure and content of cordierite.The crystalinity was estimated by rietveld refinement with X′Pert software.The phase composition was evaluated by Semi-quantification method,and the grain size of cordierite and cristobalite was calculated by Scherrer formula.The results show that crystalintiy and grain size of cordierite synthesized with decomposed magnesite and pyrophy llite increase with temperature from 1 350 ℃ to 1 400 ℃.Optimized calcination temperature is determined to be 1 400 ℃ for cordierite synthesized with decomposed magnesite and pyrophyllite.The grains of cordierite and cristobalite grow completely and the content of cordierite is 67wt%,the content of cristobalite is 33% at 1 400 ℃.Crystalintiy and grain size of crystalline phase decrease with temperature when the temperature is higher than 1 400 ℃.Decomposition of cordierite at 1 500 ℃ accelerates devitrificaiton of cristolallite.
出处
《无机化学学报》
SCIE
CAS
CSCD
北大核心
2011年第3期434-438,共5页
Chinese Journal of Inorganic Chemistry
基金
辽宁省教育厅重点实验室项目(2010年)资助
关键词
堇青石
菱镁矿风化石
叶腊石
结晶度
烧成温度
cordierite
decomposed magnesite
pyrophyllite
crystalinity
calcination temperature
