Transverse Stress Applying Technology for High-Current Superconducting Conductors Testing

Abstract

High-current superconducting conductors are widely used in fusion magnets, high energy accelerators and high magnetic field facilities. It's urgent to carry out experimental research on DC performance of new conductors to meet the development needs of these magnets. A new test facility with maximum background magnetic field of 6 T and maximum sample current of 30 kA is developed. For the purpose of preventing the sample conductors from premature quenches due to mechanical disturbance under the magnetic field, it is necessary to apply a certain transverse stress to the sample through sample support. In this paper, two different kinds of transverse stress applying technologies, active method and passive method, are developed. The general design of these two kinds of sample supports, the influence of cooling and powering process on sample transverse stress with active sample support, the assembly gap analysis of passive sample support are described in detail. The used sample supports respectively for Nb-Ti Rutherford cable, MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> Cable-in-conduit Conductors (CICC) and Bi-2212 sub-cable testing are presented. Comprehensively considering the stability margin of conductor sample and the influence of transverse stress on performance of the sample, the selection basis of transverse stress applying at room temperature is also summarized.