La^(3+),Ce^(4+)对制备堇青石材料晶相转变及烧结性能的影响  

Influence of La^(3+),Ce^(4+) on Phase Transition and Sintering Property of Cordierite Material Prepared by Solid Reaction

作　　者：罗旭东[1,2] 曲殿利[1] 谢志鹏[2] 

机构地区：[1]辽宁科技大学高温材料与镁资源学院,辽宁鞍山114051 [2]清华大学材料科学与工程系新型陶瓷与精细工艺国家重点实验室,北京100084

出　　处：《中国稀土学报》2013年第2期203-210,共8页Journal of the Chinese Society of Rare Earths

基　　金：国家"十二五"科技支撑计划资助项目(2012BAB06B01)

摘　　要：以菱镁矿风化石、工业氧化铝和二氧化硅微粉为原料,加入不同含量氧化镧、氧化铈添加剂,通过固相反应合成制备堇青石材料。用XRD法和SEM法表征试样中的晶相组成和显微结构,用X'Pert Plus软件计算主晶相的晶格常数、晶胞体积和试样的相对结晶度,用半定量法计算试样中各晶相含量,用Scherrer公式计算主晶相的粒径大小。研究分析了La3+,Ce4+对制备堇青石材料晶相组成、主晶相粒径大小、晶胞常数、试样相对结晶度、显微结构及烧结性能的影响。结果表明:氧化镧比氧化铈具有更好的助堇青石烧结性,加入氧化镧的堇青石试样具有更好的致密性;随着氧化镧、氧化铈加入量的增加,堇青石晶胞常数和晶胞体积呈现先增大后减小趋势;Ce4+更高的电场强度促进了堇青石材料更容易发生晶相转变形成莫来石。Abstract： The cordierite was prepared by solid reac tion with raw materials including decomposed magne site, industrial alumina and Si02 powder with differ ent content of lanthana, ceria as additives. The crys talline phases and microstructure were determined by XRD and SEM respectively. The lattice parameters and crystallinity of the crystalline phases were esti mated by X＇Pert plus software. The phase composition was evaluated by semiquantification method, and grain size was calculated by Scherrer formula. The effect of La3 ＋ and Ce4 ＋ on composition, grain size, lattice parameters, crystallinity, microstructure, andsintering property of cordierite materials was studied. The results showed that the sintering property of lan thana as sintering aid for cordierite materials was bet ter than that of ceria. The cordierite material added with lanthana was denser than with ceria as sintering aid. The lattice parameters and lattice volume of cor dierite were firstly increased and then decreased with the addition of lanthana and ceria. The phase transition of cordierite, Which resulted in mullite, was facilitated due to the higher ionic field intensity of Ce4＋ than that of La3＋.

关 键 词：氧化镧 氧化铈 堇青石 固相反应 晶相转变 

分 类 号：O614.22[理学—无机化学] O613.72[理学—化学]