Abstract Body

Achieving superconducting joints with large current capacities is a challenge for magnetic resonance imaging applications of REBa2Cu3O7-δ (REBCO) superconducting tapes. Here we report a novel method to fabricate a superconducting joining between two REBCO tapes using a joining strap consisting of REBCO, Ag, a buffer, and a substrate. The Ag layer serving as a fast oxygen diffusion path to promote the recovery of superconductivity of the REBCO layer during oxygenation annealing. The critical current of the superconducting joint is 116 A at 77 K, which is more than 98% that of the joined YBCO CCs. The persistent field decay of the closed-loop coil showed a joint resistance of less than 1.8Í10-15 Ω at 77 K. The atomic arrangement at the joined YBCO interface is well aligned along the (001) plane, enabling superior superconductivity. And a 0.4 Tesla REBCO magnet with persistent current mode operation has been developed based on superconducting joints.

References

Ohki K, Nagaishi T, Kato T, Yokoe D, Hirayama T, Ikuhara Y, Ueno T, Yamagishi K, Takao T, Piao R, Maeda H and Yanagisawa Y 2017 Fabrication, microstructure and persistent current measurement of an intermediate grown superconducting (iGS) joint between REBCO-coated conductors Superconductor Science and Technology 30 115017

Acknowledgment

This work was supported by the National Key R&D Program of China (No. 2022YFE03150203); the National Natural Science Foundation of China (Grant No. U2032217, Grant No. 52072366, and Grant No. 51721005); and the Youth Innovation Promotion Association of the Chinese Academy of Sciences (Y202041).