This paper deals with magnetic field dependence of transition current of NbTi mechanical persistent current switch (PCS), which realizes zero contact resistance and consists of two contact pieces made of NbTi bulk, in parallel or perpendicular magnetic field. The transition current is defined as the quench current with which the contact resistance abruptly generates. It is found that the transition current decreases with the field strength. Using a theoretical model to explain the formation mechanism of a superconducting connection at the contact of the mechanical PCS, it is confirmed that the transition current varies according to Jc-B characteristics of the contact piece material NbTi. These findings prove that NbTi mechanical PCS has superconductive connection between the contact pieces in the closed state and can be operated in persistent current mode as a superconducting PCS.
All Science Journal Classification (ASJC) codes
- Materials Science(all)
- Physics and Astronomy(all)