Journal of Applied Science and Engineering

Published by Tamkang University Press


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W. C. Chan This email address is being protected from spambots. You need JavaScript enabled to view it.1,Y. P. Yang1 and C. H.Chiang1

1Physics Department, Tamkang University, Tamsui, Taiwan 251, R.O.C.


Received: December 26, 2006
Accepted: June 30, 2007
Publication Date: June 1, 2008

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A modified close cycle helium gas cryogenic system was used to measure the flux drag torque acting on a free spinning disk magnet by a single grain YBCO superconductor. It was found that at low spinning speed ( less than 8 Hz ) and constant levitation height, the flux drag torque decreased with temperature which behavior is roughly similar to the temperature dependence of the reciprocal of critical current density for a single grain superconductor.

Keywords: Critical Current Density, Flux Pinning and Creep, Superconducting Bearings


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