Investigation of the correlation between the electrical contact resistance and the contact area of mechanical lap joint fabricated with high-temperature superconducting tapes using X-ray microtomography
Investigation of the correlation between the electrical contact resistance and the contact area of mechanical lap joint fabricated with high-temperature superconducting tapes using X-ray microtomography
复制标题
利用 X 射线显微断层扫描技术研究高温超导带机械搭接接头的接触电阻与接触面积之间的相关性
DOI：
10.1016/j.fusengdes.2019.111284
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发表时间：
2019
影响因子：
1.7
通讯作者：
Hashizume Hidetoshi
中科院分区：
文献类型：
--
作者：
Chen Weixi;Ito Satoshi;Yusa Noritaka;Hashizume Hidetoshi
提出了一种用高温超导（HTS）带制造的机械搭接接头，用于聚变反应堆的高温超导磁体的联合缠绕。该接头的适用性已得到验证，但无法得到保证，因为在整个导体冷却和通电之前，接头电阻是不可预测的。确定影响接头电阻的因素对于开发一种在室温下预测该参数的方法是必要的。在本报告中，我们评估了接触界面的电阻（接触电阻）与使用 X 射线计算机断层扫描观察到的接触面积（观察到的接触面积）之间的相关性，并讨论了用于此预测的适当技术。总共制备了 40 个机械搭接接头样品。使用图形切割图像分割从接触界面的横截面图像中分割观察到的接触区域，同时根据测量的接头电阻计算接触电阻。该相关性表明，与使用标称接触面积的传统方法相比，基于观察到的接触面积来预测接触电阻更为精确。然而，由于接触界面上的精细结构分布不均匀，一些分散的接触电阻率仍然存在。
A mechanical lap joint fabricated with high-temperature superconducting (HTS) tapes is proposed for the application to joint-winding in HTS magnets for fusion reactors. The applicability of the joint has been validated, however, it could not be guaranteed because the joint resistance is unpredictable before the entire conductor is cooled and energized. Identifying the factors that affect the joint resistance is necessary to develop a method to predict this parameter at room temperature. In this report, we evaluated the correlation between the electrical resistance of contact interfaces (contact resistance) and the contact area observed using X-ray computer tomography scan (observed contact area), and discussed appropriate techniques for this prediction. A total of 40 mechanical lap joint samples were prepared. The observed contact areas were segmented from cross-sectional images of contact interfaces using a graph cut image segmentation, while the contact resistances were calculated from measured joint resistances. The correlation indicated that the prediction of contact resistance is more precise when base on the observed contact area compared to the conventional method using the nominal contact area. However, some of dispersive contact resistivity still remained due to inhomogeneous distribution of fine-structure on contact interface.