A device for critical current versus strain measurements up to 1000 A and 17 T on 80 cm long HTS and LTS technical superconductors

Abstract

We have developed a device for the electromechanical characterization of 80 cm long technical superconducting wires carrying up to 1000 A at 4.2 K up to 17 T. Our device is based on the concept of the Walters spring (WASP), which allows us to measure long length wires (up to 80 cm) and to obtain an absolute measurement of the applied strain value. It is thus possible to measure the voltage–current relation of technical superconducting wires and tapes down to 0.1 µV cm−1, an important requirement for the characterization in view of applications like NMR high field magnets which require persistent mode operation. In this contribution, we report on Ic measurements versus strain at fields up to 17 T for industrial Nb3Sn and BSCCO: the voltage–current relation as a function of strain and magnetic field has been measured over three decades of electric field.