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 × 10−15 Ω 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 the superconducting joints development.

中文翻译：

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量身定制的接头制造工艺衍生超低电阻MgB2超导接头

摘要 我们报告了一种超低电阻超导接头，该接头使用未反应的复丝 MgB2 线材，通过在热处理条件下调整接头内的粉末压实压力来生产。该接头在 20 K 自场中表现出 5.48 × 10−15 Ω 的超低电阻和 91.3 A 的临界电流 (Ic)。接头的微观结构和成分研究分别揭示了裂纹和大量的 MgO。这两个特点在一定程度上降低了关节的Ic；尽管如此，联合抵抗并没有受到影响。我们量身定制的连接工艺将在超导接头的开发中发挥关键作用。