Stress and magnetostriction in an infinite hollow superconducting cylinder with a filling in its central hole

Abstract

In this paper, the stress and magnetostriction induced by flux pinning in an infinite hollow cylinder of type-II superconductor with a non-superconductive filling in its central hole are analytically investigated. Based on the exponent model of critical state of superconductor, the magnetic and current distributions in the hollow cylinder superconductor are obtained firstly. The stress and magnetostriction of the composite superconductive cylinder are then formulated and the magnetoelastic behaviors are characterized analytically. The results show that the hoop stress concentration near the central hole is dominant due to the tension Lorentz force and it is certainly suppressed by filling a non-superconductive material in the hole. Without change of the magnetization characteristic of the superconductor, the filling material provides effective way to remedy the stress state at the verge of the hollow in the superconductive cylinder by adjusting its Young modulus. The magnetostriction of the composite cylinder under the cycled magnetic field is further presented. Effect of the applied maximum field, complete penetration field parameter and filling material parameter on the profile of the cycled magnetostriction for the composite superconducting cylinder is discussed in detail.