Hysteresis losses and magnetic phenomena in rotating disks of type-II superconductors

Journal Article · Sat Mar 01 04:00:00 EST 1980 · J. Appl. Phys.; (United States)

DOI:https://doi.org/10.1063/1.327778· OSTI ID:5541404

Boyer, R; Fillion, G; LeBlanc, M A.R.

Hysteresis losses and the evolution of the magnetic flux threading disks of V and VTi rotating slowly in various static magnetic fields H/sub 0/ directed perpendicular to the axis of rotation have been investigated by continuously monitoring and , the average components of the magnetic induction, in the plane of the disk, parallel and perpendicular to H/sub 0/. A simple model is developed which satisfactorily accounts for the hysteresis losses and the magnetic behavior during the initial changes and in the subsequent quasi-steady-state as the rotation progresses. The analysis indicates that dpsi/dx= +- k'J/sub c/ (B) describes the change of orientation of the sheets of flux lines with respect to H/sub 0/ with distance from the flat surfaces. J/sub c/ (B) is the critical current density and k' (T) is the shearing inclination parameter of the flux lattice in the sample. Our results confirm the hypothesis that, regardless of the initial magnetic state of the disk, in regions where psi (x) varies with depth, the critical slope of the B profile (i) is diamagnetic and (ii) is not shallower than for the situations where the sheets of flux lines are parallel. We stress that point (i) requires that the rotation causes flux to escape from the disk against the gradient of B near the surface when the initial magnetic configuration is uniform or paramagnetic.

• Research Organization: Physics Department, University of Ottawa, Ottawa, Canada K1N 6N5
• OSTI ID: 5541404
• Journal Information: J. Appl. Phys.; (United States), Journal Name: J. Appl. Phys.; (United States) Vol. 51:3; ISSN JAPIA
• Country of Publication: United States
• Language: English

Related Subjects

420201* -- Engineering-- Cryogenic Equipment & Devices
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
CURRENT DENSITY
DATA
ENERGY LOSSES
HYSTERESIS
INFORMATION
LOSSES
MAGNETIC FIELDS
MAGNETIC FLUX
MAGNETIC PROPERTIES
MATHEMATICAL MODELS
ORIENTATION
PHYSICAL PROPERTIES
SHEAR
STEADY-STATE CONDITIONS
SUPERCONDUCTORS
TYPE-II SUPERCONDUCTORS