Nb3Sn超导块体的制备及超导性能研究  

Fabrication and Superconducting Properties of Nb3Sn Superconducting Bulks

作　　者：邱庆航 索红莉[1] 程军胜[2] 张子立[1,2] 纪耀堂 王秋良 Qiu Qinghang;Suo Hongli;Cheng Junsheng;Zhang Zili;Ji Yaotang;Wang Qiuliang(College of Materials and Engineering y Beijing University of Technology,Beijing 100124,China;Institute of Electrical Engineering,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)

机构地区：[1]北京工业大学材料科学与工程学院,北京100124 [2]中国科学院电工研究所,北京100190 [3]中国科学院大学,北京100049

出　　处：《稀有金属》2020年第2期166-171,共6页Chinese Journal of Rare Metals

基　　金：国家自然科学基金项目(51827810,11745005);北京市科技计划课题(Z181100003818020);中国科学院国际伙伴计划项目(GJHZ1806,GJHZ1883)资助。

摘　　要：Nb3Sn超导材料在10 T以上高场条件下具有良好的超导性能,高场磁体设备中的Nb3Sn超导接头可以用Nb3Sn超导块体连接。采用粉末冶金工艺制备了Nb3Sn超导块材,研究了成型压力和球磨对Nb3Sn超导块体成相及超导性能的影响,利用X射线衍射仪(XRD)和扫描电子显微镜(SEM)对不同制备条件下的混合粉末与热处理后的Nb3Sn超导块材进行了物相分析和表面形貌的表征,利用综合物性测试系统(PPMS)分析了不同Nb3Sn块材的超导性能和块体中的超导相含量。结果表明:粉末成型压力对块体致密度有较大影响,压力为30 MPa时粉末块体的密度为8.03 g·cm-3,压力增加到40 MPa时密度几乎不再增加;粉末的球磨时间会影响平均颗粒度,当球磨时间为15 h,原始粉末的平均颗粒度由100μm减小到10μm左右;不同球磨时间的样品超导转变温度(Tc)差别不大,但是时间越长临界电流密度(Jc)相对更高。通过优化制备工艺最终制备出Tc为17.6 K, 10 T背场下Jc为150 A·mm-2的Nb3Sn超导块体。Nb3Sn has good superconducting properties in the background magnetic field above 10 T, Nb3Sn superconducting joints in high field magnet equipment can be connected with Nb3Sn superconducting bulks. By fabricating different powder metallurgy Nb3Sn superconducting bulks, the effects of pressure and ball milling on Nb3Sn phase formation and superconducting properties were investigated. X-ray diffraction(XRD) and scanning electron microscope(SEM) were used to analyze the phase composition and surface microstructure of mixed powder and heat-treated Nb3Sn bulks on different preparation conditions. Physical property measurement system(PPMS) was used to analyze the superconducting properties and superconducting phase content of different Nb3Sn bulks. The results suggested that the pressure of powder shaping had a great influence on the density of the bulks, When the pressure was 30 MPa, the density of the bulk was 8.03 g·cm-3, but the density hardly increased when the pressure up to 40 MPa. The average particle size of powders would be affected by the milling time, when the ball milling time was 15 h, the average particle size of the original powder was reduced from 100 μm to about 10 μm. The superconducting transition temperature(Tc) of the samples with different ball milling time had little difference, but the longer the time, the higher the critical current density(Jc). By changing the pressure and ball milling time, Nb3Sn superconducting bulks were obtained successfully and its critical transition temperature was 17.6 K, critical current density was 150 A·mm-2 under the background magnetic field of 10 T.

关 键 词：Nb3Sn超导体 粉末冶金 球磨 超导临界性能 

分 类 号：TG146[一般工业技术—材料科学与工程]