卷绕法Nb3Al长线热处理工艺、微观结构及超导性能研究  

Heat-treatment and Superconducting Properties of Jelly-roll Nb_3Al Superconducting Wire

作　　者：孙霞光 潘熙锋[2] 李平原[1] 闫果[2] 冯勇[2] 张平祥[2] 赵勇[1] SUN Xiaguang;PAN Xifeng;LI Pingyuan;YAN Guo;FENG Yong;ZHANG Pingxiang;ZHAO Yong(Key Laboratory of Advanced Technologies Materials,Ministry of Education,Southwest Jiaotong University,Chengdu 610031,China;Western Superconducting Technologies Co.Ltd（WST）,National Engineering Laboratory for Superconducting Materials,Xi＇an 710018,China)

机构地区：[1]西南交通大学材料先进技术教育部实验室,成都610031 [2]西部超导材料科技股份有限公司,超导材料制备国家工程实验室,西安710018

出　　处：《低温物理学报》2018年第4期19-24,共6页Low Temperature Physical Letters

基　　金：国家自然科学基金项目(No.51377138和51877180);国家磁约束核聚变能研究专项(2017YFE301401);国家国际科技合作专项(No.2013DFA51050)资助的课题.

摘　　要：本文采用卷绕法(Jelly-roll),结合静液挤压、拉拔和轧制等方式制备了Nb_3Al超导线材前驱体长线,利用自主设计制作的长线急热急冷(～2000℃,RHQ)装置对线材进行RHQ热处理,随后对线材样品进行了表面覆铜处理和低温成相热处理.通过对比不同加热电流、不同走线速度对最终线材低温超导特性的影响,获得了高性能Nb_3Al超导长线最佳热处理条件.结果表明:生成的Nb_3Al超导线材T_c达到17.4K,临界电流密度J_c在4.2K、12T下达到1170A/mm^2.SEM分析表明:该最佳热处理条件下,Nb和Al原子相互充分扩散,生成原子比3:1的Nb_3Al超导体、而且晶粒较小.In this work, we utilized Jelly-roll method to make the Nb3Al precursor long wires, combing with hydrostatic-extrusion, drawing and rolling process, and consequently high-performance Nb3Al superconducting wires had been made, which stood up a rapid heating, quenching （RHQ） process by using the home-made RHQ equipment up to 2000℃ and low-temperature annealing process. The optimum RHQ heat-treatment conditions of the high-performance Nb3Al superconducting wires were obtained through investigating the RHQ parameters of heating current and wire speed. The results suggest that the T, of Nb3Al superconducting wire is 17.4 K and the critical current density （Jc） reaches 1170 A/mm^2 at 4.2 K and 12 T, which is promising to develop the next- generation high-performance Nb3Al superconducting wires for high-field magnet application. And the SEM measurements present Nb and Al atoms in the precursor wires are fully diffused each other to get Nb3AI superconductors with Nb/Al atom ratio of 3：1 under the optimum heat-treatment condition. In particular, the high critical current density imply that the Nb3 Al superconductors fabricated under the optimum condition are with fine grain.

关 键 词：Nb3Al 超导线材 卷绕法 急热急冷热处理(RHQ) 

分 类 号：TM26[一般工业技术—材料科学与工程] TG156[电气工程—电工理论与新技术]