Influence of Wall Thickness on Magnetic Shielding Effects of BPSCCO Cylinders

  • Mineo Itoh
Part of the An International Cryogenic Materials Conference Publication book series (ACRE, volume 40)


The critical current density (J c ) of high critical temperature (T c ) superconductor is an important parameter in magnetic shielding. However, it is difficult to fabricate very high-J c material. The present research group has been improving magnetic shielding effects for high-T c , superconducting cylinders by using special techniques. As one of the basic research areas for the improvement of magnetic shielding effects and the fabrication of large sized cylinders, the present paper analyzes the relationship between the wall thickness (w) of the cylinder and the maximum magnetic shielded field (B s ) by use of critical state models. The values of B s are systematically measured by changing the w values of BPSCCO cylinders at a temperature of 77.4 K. It is found that the values of B s do not change linearly with the values of w, and the theoretical values of B s agree well with the experimental values. The temporal change of the maximum magnetic trapped field (B t ) is also analyzed by Anderson-Kim flux-creep theory, with the experimental results of the temporal change of B t agreeing well the theoretical results. It is observed the periodic dependence of DC-SQUID voltage on the applied magnetic field in the center of the superconducting cylinder.


Applied Magnetic Field Critical Current Density Effective Shield Critical State Model Cold Isostatic Press 
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© Springer Science+Business Media New York 1994

Authors and Affiliations

  • Mineo Itoh
    • 1
  1. 1.Department of Electronic Engineering Faculty of Science and TechnologyKinki UniversityHigashi-Osaka, Osaka 577Japan

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