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arXiv · 1911.12645

Tailored joint fabrication process derived ultra-low resistance MgB2 superconducting joint

Dipak Patel·Akiyoshi Matsumotoa·Hiroaki Kumakura·Gen Nishijima·Minoru Maeda·Su-Hun Kim·Seyong Choi·Jung Ho Kim
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Abstract

We report an ultra-low resistance superconducting joint using unreacted multifilament MgB2 wires produced by tailoring the powder compaction pressure within the joint with heat treatment conditions. The joint demonstrated an ultra-low resistance of 5.48 x 10^-15 ohms and critical current (Ic) of 91.3 A at 20 K in self-field. The microstructural and composition studies of the joint revealed cracks and a high amount of MgO, respectively. These two features reduced the Ic of the joint to some extent; nevertheless, the joint resistance was not affected by it. Our tailored joining process will play a pivotal role in superconducting joint development.

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Dipak Patel, Akiyoshi Matsumotoa, Hiroaki Kumakura, Gen Nishijima, Minoru Maeda, Su-Hun Kim, Seyong Choi, Jung Ho Kim. 2019-11-28. Tailored joint fabrication process derived ultra-low resistance MgB2 superconducting joint. https://doi.org/10.1016/j.scriptamat.2019.11.020

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