(La_(0.75)Sm_(0.25))_2Zr_2O_7纳米粉体的高温动态XRD研究  

High temperature dynamic XRD research of (La_(0.75)Sm_(0.25))_2Zr_2O_7 nano powder

作　　者：蔡辉[1] 张锦化[1,2] 柯昌明[1] 吴红丹[2] 于吉顺[2] 

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]中国地质大学(武汉)地质过程与矿产资源国家重点实验室,湖北武汉430074

出　　处：《耐火材料》2013年第3期177-179,183,共4页Refractories

基　　金：地质过程与矿产资源国家重点实验室科技部专项资助项目(MSFGPMR201204)

摘　　要：采用化学共沉淀-高温煅烧技术制备的具有烧绿石结构的(La0.75Sm0.25)2Zr2O7纳米粉体,其平均晶粒尺寸约为47 nm,其晶体结构为等轴晶系,空间群为F d-3m,晶胞参数a0=1.075 nm。采用高温动态XRD技术研究了(La0.75Sm0.25)2Zr2O7纳米粉体的热稳定性、热膨胀性及抗烧结性能。结果表明:(La0.75Sm0.25)2Zr2O7纳米粉体具有良好的热稳定性,高温下晶体结构仍保持稳定,1 400℃的热膨胀系数为9.7×10-6K-1;具有优异的抗高温烧结性能,1 250℃以上纳米晶粒才开始快速生长,1 400℃时,晶粒尺寸为132 nm。（ La0.75 Sm0.25 ）2Zr2O7 nano powders with pyrochlore structure were prepared by chemical co-dep- osition-high temperature calcination method. The average grain size of the powders is about 47 nm. The crystal structure is cubic system;space group is F d-3m;cell parameter ao = 1. 075 nm. The thermal stabili- ty,thermal expansion and sintering resistance of the powders were investigated by high temperature dy- namic XRD. The results show that the （ La0.75 Sm0.25 ）2Zr2O7 nano powders exhibit a good thermal stability with a stable crystal structure at high temperatures,and a thermal expansion coefficient of 9.7×10^6K^-1 at 1 400 ℃;the powders display an excellent sintering resistance at high temperatures; nanocrystals begin to grow rapidly at 1 250 ℃ above,and the grain size is 132 nm at 1 400 ℃.

关 键 词：( LA0 75 SM0 25 )2Zr2O7纳米粉体 高温动态XRD分析 热稳定性 热膨胀性 抗烧结性 

分 类 号：TB321[一般工业技术—材料科学与工程] TG115.2[金属学及工艺—物理冶金]