CeO_2对MgO-CaO材料性能的影响  

Effect of CeO_2 on properties of MgO-CaO materials

作　　者：张寒[1,2] 赵惠忠[1,2] 陈金凤[1,2] 李静捷 余俊[1,2] 聂建华[1] 

机构地区：[1]武汉科技大学耐火材料与高温陶瓷国家重点实验室培育基地,湖北武汉430081 [2]武汉科技大学纳米材料与技术中心,湖北武汉430081

出　　处：《耐火材料》2014年第1期36-38,42,共4页Refractories

基　　金：国家自然科学基金资助项目(50774057)

摘　　要：以分析纯Mg(OH)2、Ca(OH)2为原料,按m(MgO)m(CaO)=75 25配料,并分别加入质量分数为0、0.5%、0.75%、1%的分析纯CeO2为掺杂剂,通过行星球磨机混合后机压成型,经1 650℃3 h热处理,制备了MgO-CaO材料。通过XRD、SEM及四探针高温电导率测定仪对试样进行了分析。结果表明:随CeO2掺入量的增大,试样的体积密度逐渐增大,显气孔率减小,致密化程度增强;在烧结致密化过程中,试样晶粒间的气孔逐渐减少,但MgO晶粒中的气孔逐渐增多,而CaO晶粒中未有气孔出现;CeO2的引入可增强试样的导电性能,其实质在于CeO2与CaO发生置换固溶,增大了Ca2+空位的浓度,有利于Ca2+的扩散。MgO-CaO materials were prepared using analytically pure Mg （OH） 2 and Ca （OH） 2 as starting materials （mass ratio of MgO and CaO =75：2.5） and analytically pure CeO2（O,0. 5% ,0.75% ,and 1% ） as dopant,mixing by a planetary ball mill, pressing,then firing at ] 650 ℃ for 3 h. The prepared specimens were characterized by XRD, SEM and a four-probe high temperature electric conductivity meter. The results show that with the increase of CeQ addition,the bulk density increases,the apparent porosity decreases and the densification of MgO-CaO materials promotes; in the sintering densification process, pores in specimens gradually decrease while pores among MgO grains gradually increase and no pore is observed among CaO grains;the addition of CeO2 can improve the electric conductivity of MgO-CaO materials;the nature lies in the substitution and solid solution between CeQ2 and CaQ,which enlarges the vacancy concentration of Ca2＋ and accelerates the diffusion of Ca2＋.

关 键 词：氢氧化镁 氢氧化钙 气孔 导电性能 

分 类 号：TQ175[化学工程—硅酸盐工业]