第二代高温超导带材焊接及力学性能研究  

Study on Welding Joint and Its Mechanical Performance of 2G-HTS Tape

作　　者：张永军 孙佳阳 胡宏伟 陆齐 刘志勇 鲁玉明[1,2,3] 郭艳群 菅洪彬[1] 豆文芝 蔡传兵[1,2,3] ZHANG Yongjun;SUN Jiayang;HU Hongwei;LU Qi;LIU Zhiyong;LU Yuming;GUO Yanqun;JIAN Hongbin;DOU Wenzhi;CAI Chuanbing(Shanghai Creative Superconductor Technologies Co.,Ltd.(SCSC),Shanghai 201401,China;Shanghai Key Laboratory of High Temperature Superconductors,Shanghai 200444,China;Physics Department of Shanghai University,Shanghai 200444,China)

机构地区：[1]上海上创超导科技有限公司,上海201401 [2]上海大学物理系,上海200444 [3]上海市高温超导重点实验室,上海200444

出　　处：《低温物理学报》2021年第6期354-363,共10页Low Temperature Physical Letters

摘　　要：第二代高温超导已进入产业化初期,尽管单根带材长度已达千米量级,但由于千米级单根带材生产成品率偏低以及大型超导装置对带材长度实际需求远超出单根长度制备能力,因此,焊接技术成为高温超导大规模应用的关键技术之一.接头电阻及其力学性能是评估焊接接头的重要技术指标.本文提出了改进型接头和“隐形”接头两种制作方法,并对其接头电阻以及力学性能进行了表征,同时与常规搭接接头进行了对比分析.结果发现,(1)与常规搭接头相比,改进型和“隐形”接头的厚度分别降低了15%和36%,有效减小了焊接头处和原带材厚度差异.(2)超导面-超导面焊接,获得接头电阻最小;接头电阻随接头长度的增加而减小,但幅度降低.(3)常规搭接头、改进型和“隐形”焊接头均具有良好的轴向抗拉性能,通过扭转和8天液氮浸泡后,临界电流无衰退,电阻保持一致.(4)改进型和“隐形”接头的临界弯曲直径(20 mm)与原带材(非接头处)相当,通过卷对卷传输法测试时接头无损伤,而常规搭接头的临界弯曲直径(40 mm)大于原带材,在通过卷对卷测试时,接头出现开裂甚至断开现象.根据具体应用场景,选择合适接头制作方式,对推动第二代高温超导产业化具有重要意义.At present,the second-generation high temperature superconductor(2 G-HTS)has entered the initial stage of industrialization.On the one hand,even though the length of its single piece reaches up to 100 m,even 1000 m,the yield of production is low because of complex production processes.On the other hand,the practical demand for single piece tapesfar exceeds its single preparation capacity in preparation of large superconducting devices.Therefore,Welding technology has become one of the key technologies for the large-scale application of the second-generation high temperature superconductor.Joint resistance and its mechanical properties are known as important technical indexes for evaluating welded joints.In this paper,two kinds of joints newly developed,improved joint(2#-joint)and“invisible”joint(3#and 4#-joint),were prepared,and their joint resistance and mechanical properties were characterized.While the differences between the two joints above and conventional lap welding joints(1#-lap joint)were analyzed.The results are as follows.(1)Compared with the conventional lap joint,the thickness of the improved and"invisible"joint is reduced by 15%and 36%,respectively.Through visual inspection,the difference of thickness between the"invisible"joint and the non-joint is reduced and not distinguished,which effectively improves the probability of mechanical damage in subsequent application;(2)The minimum joint resistance is achieved for YBCO side-YBCO side wielding.For conventional welded joints,when the joint length is less than 2 cm,the joint resistance decreases linearly with the joint length;when the joint length is>2 cm,the joint resistance decreases nonlinearly with the joint length;(3)The tensile strength of conventional lap joint,improved joint and“invisible”joint at room temperature is equivalent to that of non-joint tape.All of them have good axial tensile properties.After the experiment of torsion and 8-day liquid nitrogen immersion,superconducting performance did not decline and the joint resistance i

关 键 词：第二代高温超导 焊接接头 接头电阻 力学性能 

分 类 号：TM26[一般工业技术—材料科学与工程]