Magnetic bearing element for a rotor shaft using high-T.sub.C superconducting materials

A magnetic bearing element for a rotor shaft having radially restoring magnetic forces in the event of a deflection of the rotor shaft from a reference position, said element comprising:

• a) a rotor body containing a first bearing part attached to the rotor shaft;
• b) a second, fixed-position bearing part surrounding said rotor body;
• c) one of the two bearing parts containing an arrangement of a plurality of alternately and axially polarized permanent magnetic elements which are mutually set apart by intervening spaces, said spaces each being completely filled in by an intermediate element made of a ferromagnetic material;
• d) the other of the two bearing parts having a structure including high-T.sub.c superconducting material;
• e) the rotor shaft, in at least one tubular edge area facing the first bearing part, having a non-magnetic material;
• f) the ferromagnetic intermediate elements serving to concentrate the magnetic flux exiting from the permanent magnetic elements on the side facing the superconducting structure;
• g) the superconducting structure having grains made of the high-T.sub.c superconducting material, of which the majority each have an average grain size which is larger than at least the axial thickness of each of the permanent magnetic elements.