Journal
IEEE TRANSACTIONS ON APPLIED SUPERCONDUCTIVITY
Volume 25, Issue 3, Pages -Publisher
IEEE-INST ELECTRICAL ELECTRONICS ENGINEERS INC
DOI: 10.1109/TASC.2014.2372614
Keywords
Bi2212; effective filament diameter; hightemperature superconductors; magnetization; multifilamentary superconductors; superconducting filaments and wires
Funding
- Office of Science, Division of High Energy Physics, U.S. Department of Energy [DE-SC0010312, DE-SC0011721]
Ask authors/readers for more resources
Suppression of magnetization and effective filament diameter d(eff) with twisting was investigated for a series of recent Bi2212 strands manufactured by Oxford Superconducting Technologies. We measured magnetization as a function of field (out to 14 T), at 5.1 K, of twisted and nontwisted 37 x 18 double restack design strands. The samples were helical coils 5-6 mm in height and approximately 5 mm in diameter. The strand diameter was 0.8 mm. The magnetization of samples having twist pitches of 25.4, 12.7, and 6.35 mm were examined and compared to nontwisted samples of the same filament configuration. The critical state model was used to extract the 12-T d(eff) from magnetization data for comparison. Twisting the samples reduced d(eff) by a factor of 1.5-3. The deff was shown to increase both with L and Lp. Mathematical expressions, based upon the anisotropic continuum model, were fit to the data, and a parameter.2, which quantifies the electrical connectivity perpendicular to the filament axis, was extracted. The bundle-to-bundle connectivity along the radial axis was found to be approximately 0.2%. The d(eff) was substantially reduced with Lp. In addition, the importance of understanding sample length dependence for quantitative measurements is discussed.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available