Microstructure and stopped growth mechanism of Y123 bulk fabricated by directional infiltration and growth  

作　　者：董昊 胡锐 李金山 寇宏超 薛祥义 常辉 曹海涛 周廉 

机构地区：[1]State Key Laboratory of Solidification Processing,Northwestern Polytechnical University [2]Northwest Institute for Nonferrous Metal Research

出　　处：《中国有色金属学会会刊：英文版》2008年第5期1139-1144,共6页Transactions of Nonferrous Metals Society of China

基　　金：Project(50432050) supported by the National Natural Science Foundation of China

摘　　要：The infiltration-growth process was used as an alternative to conventional melt processing techniques for the preparation of bulk YBa2Cu3O7-x(Y123) with finely dispersed small size Y2BaCuO5(Y211) particles.Bulk YBCO superconductors with uniformly distributed particles of micron-sized Y211 were prepared by the directional infiltration and growth(DIG).The microstructure changes of the Y211 particles at various stages of processing were studied.About 70% of Y211 particles are under 1 μm in the final sample.The different stopped growth mechanism of this material along the c axis and ab plane was discussed.Undercooling and viscosity lead to tanglesome thick boundary layer.So the Y123 growth along c axis is stopped.Yttrium lack in front of the ab plane is the main reason why the growth stops at this direction.The infiltration-growth process was used as an altemative to conventional melt processing techniques for the preparation of bulk YBa2Cu3O7-x（Y123） with finely dispersed small size Y2BaCuO5（Y211） particles. Bulk YBCO superconductors with uniformly distributed particles of micron-sized Y211 were prepared by the directional infiltration and growth（DIG）. The microstructure changes of the Y211 particles at various stages of processing were studied. About 70% of Y211 particles are under 1 μm in the final sample. The different stopped growth mechanism of this material along the c axis and ab plane was discussed. Undercooling and viscosity lead to tanglesome thick boundary layer. So the Y123 growth along c axis is stopped. Yttrium lack in front of the ab plane is the main reason why the growth stops at this direction.

关 键 词：熔渗作用 Y211 YBCO 超导体 

分 类 号：O511.3[一般工业技术—材料科学与工程]