Magnetostriction-induced stress in an orthotropic mechanical thin high-temperature superconducting disk based on the exponential model of critical state

Abstract

In this paper, the magnetostriction and stress of an orthotropic mechanical high-temperature superconducting disk with a concentric small hole are investigated based on the exponential model of the critical state. Approximate solutions of the displacement and stress for the superconducting disk during zero-field cooling (ZFC) and field-cooling (FC) processes are obtained. The results show that tensile stresses will appear in the disk during the decreasing field of ZFC, while the stresses are always compressive during the increasing field of ZFC and FC processes. This indicates that the superconducting disk is easily damaged during the decreasing field of ZFC and FC processes. The critical point where tensile stress is largest is provided. The value of magnetostriction depends on the size of the disk, the applied field and the magnetization process. This research is helpful in the reliability design of high-temperature superconducting disks and cables with high strength for space solar power stations.