Relaxations of levitation properties in high Tcsuperconducting (HTSC) magnetic bearings are known to revealdifferent behaviors on the ascending and descending branches oftheir force-displacement curves, i.e. the relaxations on theascending branch seem to be reduced more than those on thedescending one. In this paper, the effect has been theoreticallyillustrated in a superconducting half-space based on the Beanmodel and interpreted by the hysteretic behaviors of shieldingcurrent. Numerical simulations on the relaxation of levitationforces have been carried out, taking the hysteresis effect ofshielding current into account. The relaxations of levitated heights(displacements) have also been evaluated numerically andsimulated results were compared with measured data. The effectimproves the levitation characteristics both in calculations andexperiments. Furthermore, the practical applications of the abovementioned effect (referred to a Hysteresis Hardening Effect) arealso discussed.
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