CaCuO2颗粒尺寸对双粉法制备Bi系高温超导带材性能的影响  

Influence of CaCuO2 Particle Size on Phase Evolution of Bi-based High Temperature Superconductors Prepared by Two-powders Route

作　　者：张胜楠[1] 黄英健 马小波[4] 崔利军 刘国庆[4] 郑会玲[4] 徐晓燕[4] 焦高峰[4] 李成山[4] 冯建情[4] 闫果 张平祥 Zhang Shengnan;Huang Yingjian;Ma Xiaobo;Cui Lijun;Liu Guoqing;Zheng Huiling;Xu Xiaoyan;Jiao Gaofeng;Li Chengshan;Feng Jianqing;Yan Guo;Zhang Pingxiang(Northwest Institute for Nonferrous Metal Research,Xi’an 710016,China;Xi’an University of Technology,Xi’an 710048,China;Western Superconducting Technologies Co.,Ltd,Xi’an 710018,China)

机构地区：[1]西北有色金属研究院超导材料研究所,陕西西安710016 [2]西安理工大学,陕西西安710048 [3]西部超导材料有限公司,陕西西安710018 [4]西北有色金属研究院,陕西西安710016

出　　处：《稀有金属材料与工程》2020年第5期1469-1475,共7页Rare Metal Materials and Engineering

基　　金：National Natural Science Foundation of China(51472206);National ITER Program of China(2013GB110001);National Key Research and Development Program of China(2017YFB0902303)。

摘　　要：通过基于共沉淀工艺的双粉法制备了Bi1.76Pb0.34Sr1.93Ca2.0Cu3.06O8+δ(Bi-2223)前驱体粉末。在这一过程中,首先单独制备了Bi1.76Pb0.34Sr1.93CaCu2.06O8+δ(Bi-2212)和CaCuO2 (实际相组成为Ca2CuO3和CuO)粉末,并分别进行了烧结。通过调节共沉淀工艺过程中的pH值,获得了颗粒尺寸不同的CaCuO2粉末,然后将Bi-2212与CaCuO2粉末按照相组成1:1进行混合,并装入Ag包套中,通过一系列的旋锻、拉拔和轧制工艺,获得设计尺寸的Bi-2223带材。比表面积测试表明随着pH值从3.0增加到5.0和6.5,获得CaCuO2粉末的平均颗粒尺寸从1.10mm减小到0.75和0.60mm。通过扫描电镜对不同尺寸CaCuO2颗粒制备的Bi-2223生带、第1次热处理和后处理之后带材的相组成和分布进行了表征。结果表明,适当尺寸的CaCuO2颗粒可以避免团聚现象的出现,因此有利于高载流性能带材的获得。最终通过进一步调节带材的尺寸,1#带材的性能最高,电流密度达到了约12 200 A·cm-2。Bi1.76Pb0.34Sr1.93Ca2.0Cu3.06O8+δ(Bi-2223)precursor powders were fabricated with a two-powder route based on co-precipitation process.During this process,Bi1.76Pb0.34Sr1.93CaCu2.06O8+δ(Bi-2212)and CaCuO2(with the actual phase composition of Ca2CuO3 and CuO)powders were first synthesized and calcined separately,and then mixed together before packed into Ag sheath.By adjusting the pH values during the co-precipitation process,CaCuO2 powders with different average particle sizes of about 1.10,0.75,and 0.60mm were obtained.Then single filament Bi-2223/Ag tapes were fabricated by powder in tube(PIT)process with precursor powders obtained by mixing the different particle sized CaCuO2 powders and well-calcinated Bi-2212 powders.The influences of CaCuO2 particle size on microstructure,phase evolution dynamics and superconducting current capacity of sintered Bi-2223 tapes were studied.Results show that due to higher uniformity of Ca2CuO3 and CuO distribution in filaments,clustering of secondary phases and insufficiently reacted areas are effectively avoided.Therefore,higher current density of^12200 A·cm^-2 is obtained for the 1#tape by further optimizing the final dimension of the tapes.

关 键 词：高温超导材料 BI-2212 前驱体粉末 相演变动力学 微结构 

分 类 号：TG316[金属学及工艺—金属压力加工] TG335TG356