Y2O3添加对 Nb2O5低膨胀陶瓷结构与性能的影响  

Influence of Y_2O_3 Addition on Microstructure and Properties of Nb_2O_5-based Low Expansion Ceramics

作　　者：巫春荣[1] 张小珍[1] 冯均利[2] 周健儿[1] 章婧[1] 江瑜华[1] 

机构地区：[1]景德镇陶瓷学院材料科学与工程学院,江西省先进陶瓷材料重点实验室,景德镇333403 [2]深圳出入境检验检疫局工业品榆验技术中心,深圳518067

出　　处：《人工晶体学报》2014年第5期1130-1136,共7页Journal of Synthetic Crystals

基　　金：国家科技支撑计划课题(2011BAC11B08);江西省科技支撑计划项目(20112BBE5009)

摘　　要：采用高温固相烧结法制备了Y2O3改性Nb2O5低膨胀陶瓷材料。研究了Y2O3添加量对Nb2O5陶瓷的物相组成、微观结构、气孔率、热膨胀性能、抗弯强度和抗热震性能等的影响。结果表明，经1390℃保温2h烧成，纯Nb2O5陶瓷样品存在开裂现象，表现出低的抗弯强度和差的抗热震性能。添加2～10％Y2O3，后，样品主晶相为单斜相Nb2O5，还生成了YNbO4晶相。通过添加适量Y2O3改性，可抑制Nb2O5陶瓷烧成过程中的晶粒增长和避免开裂现象，形成致密的微观结构，样品的抗弯强度和抗热震性能显著提高。Nb2O5陶瓷的热膨胀系数随Y2O3添加量的增加而逐渐增大。Y2O3添加量为6％时，样品的热膨胀系数和抗弯强度分别为1．9×10^-6／℃和103．4MPa，表现出良好的抗热震性能。Yttria （Y2O3） modified niobium pentoxide （ Nb2O5） low expansion ceramic materials were prepared by high temperature solid-state sintering technique. The influences of Y2O3 content on the phase composition, microstructure, apparent porosity, thermal expansion performance, bending strength and thermal shock resistance of prepared Nb2O5 ceramics were investigated. The results show that the pure Nb2O5 ceramic, composed of monoclinic phase Nb2O5, shows obvious microcracking phenomena, and exhibits low bending strength and bad thermal shock resistance after sintered at 1390 ℃ for 2 h. Minor YNbO4 crystalline phase is formed with the addition of 2%-10% Y2O3. The addition of appropriate amount of Y2O3 could inhibit the growth of Nb2O5 grains during the sintering process and avoid the generation of microcracks to form a dense microstructure. The Nb2O5 ceramics modified by Y2O3, demonstrate significantly increased bending strength and thermal shock resistance. The thermal expansion coefficient （TEC） of samples increases gradually as the Y2O3 content iucreaseing. The prepared Nb2O5 ceramic with the addition of 6% Y2O3 shows a TEC of 1.9× 10 -6/℃, bending strength of 103.4 MPa and excellent thermal shock resistance.

关 键 词：低膨胀陶瓷 五氧化二铌 氧化钇 热膨胀性能 抗弯强度 抗热震性 

分 类 号：TQ174.75[化学工程—陶瓷工业]