Contact resistance characteristics of high temperature superconducting bulk-III

A persistent current switch (PCS) is used for superconducting applications, such as superconducting magnetic energy storage (SMES) system. We have proposed a mechanical switch of high-temperature superconductor (HTS) as a mechanical PCS. In the previous paper, the sample surfaces were carefully polished and deposited with metals. As a result, the transfer current exceeded 30 A, and the contact resistance reduced to 6 μΩ at constant load 500 N. In This work, the experiment result when depositing metal thickly, and the relation between contact resistance and load were reported. Reduction of contact resistance and load was tried by depositing metals. Consequently, contact resistance could be reduced. When depositing indium, the increase of contact resistance by load reduction could be suppressed. Additionally, based on the experimental results and surface observation, we analyzed the current density and temperature distribution of the switch with finite element method (FEM). This analysis result may lead to the elucidation of a contact mechanism.