Performance of Nd-Fe-B and ferrite magnets in superconducting linear bearings with bulk YBCO

Author

De Andrade, R., Jr. ; Cardoso, J.A.A.S. ; dos Santos, G.C. ; de Cicco, L.B. ; Fernandes, A.F.G. ; Rosario, M.A.Pd. ; Neves, M.A. ; de Souza, A.P. ; Ripper, A. ; da Costa, G.C. ; Nicolsky, R. ; Stephan, R.M.

Author_Institution

LASUP/UFRJ, Rio de Janeiro, Brazil

Volume

13

Issue

2

fYear

2003

fDate

6/1/2003 12:00:00 AM

Firstpage

2271

Lastpage

2274

Abstract

The performance of two different magnets has been tested in linear bearings with YBCO bulk superconductors, prepared by seeded melt texturing technique. Two different rails have been assembled with opposite magnetic polarization and intercalation of ferromagnetic flux concentrators. One rail has been mounted with Nd-Fe-B magnets and the other one, with Ferrite magnets. The levitation force of the Nd-Fe-B permanent magnets rail is more than one order of magnitude larger than that one of Ferrite. The stiffness of the linear bearing and the vibration damping were measured in the field cooling procedure for several cooling heights from the rail. The different cooling heights result in different gaps between the YBCO blocks and the magnets, for the same load. The stiffness increases with the decrease of gap, for the same load, in both cases, but is higher in the Nd-Fe-B rail. The vibration damping is rather low in both systems (∼0.01). We conclude that the Nd-Fe-B magnets are the most suitable for applications on linear levitating bearings.

Keywords

barium compounds; boron alloys; ferrites; high-temperature superconductors; iron alloys; magnetic bearings; magnetic levitation; neodymium alloys; permanent magnets; yttrium compounds; Nd-Fe-B; Nd-Fe-B magnet; YBCO bulk superconductor; YBaCuO; ferrite magnet; ferromagnetic flux concentrator; field cooling; levitation force; linear bearing; magnetic polarization; permanent magnet; rail; seeded melt texturing; stiffness; superconducting magnetic bearing; vibration damping; Cooling; Damping; Ferrites; Magnetic levitation; Rails; Superconducting magnets; Superconductivity; Testing; Vibration measurement; Yttrium barium copper oxide;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2003.813063

Filename

1212073