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arXiv · 2109.14300

High-performance Ba1-xKxFe2As2 superconducting joints for persistent current operation

Yanchang Zhu·Dongliang Wang·Qiqi Wang·Wenwen Guo·Cong Liu·He Huang·Hongjun Ma·Fang Liu·Huajun Liu·Yanwei Ma
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Abstract

Superconducting joints are one of the key technologies to make Ba1-xKxFe2As2 (Ba-122) superconducting wires or tapes for high-field applications. Herein, superconducting joints were fabricated by a simple cold-pressing method, and the joint resistance of the iron-based superconducting joint was estimated for the first time. The superconducting properties, microstructures, and elements distribution in the joint regions were investigated. At 4.2 K and 10 T, a transport critical current Ic of 105 A for the joint was obtained, and the critical current ratio (CCR= Ic-joint/Ic-tape) of the joint was 94.6%. On the other hand, the joint show very low joint resistance of 2.7x10^-13 ohm in self-field at 4.2 K. Among iron-based superconductors (IBS), this work is the first to successfully realize a superconducting joint with such high CCR and low joint resistance. This work shows great potential to apply Ba-122 in a range of practical applications, where superconducting joints are essential.

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Yanchang Zhu, Dongliang Wang, Qiqi Wang, Wenwen Guo, Cong Liu, He Huang, Hongjun Ma, Fang Liu, Huajun Liu, Yanwei Ma. 2021-09-29. High-performance Ba1-xKxFe2As2 superconducting joints for persistent current operation. https://doi.org/10.1088/1361-6668/ac4ff1

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