DocumentCode :
1528107
Title :
Effect of twisting on the filaments of multifilamentary BSCC0(2223)/Ag and /AgMg tapes
Author :
Goldacker, W. ; Eckelmann, H. ; Quilitz, M. ; Ullmann, B.
Author_Institution :
Inst. fur Tech. Phys., Forschungszentrum Karlsruhe, Germany
Volume :
7
Issue :
2
fYear :
1997
fDate :
6/1/1997 12:00:00 AM
Firstpage :
1670
Lastpage :
1673
Abstract :
For reduced AC losses of multifilamentary BSCC0(2223) tapes, it is necessary to apply a twist to the filaments along the tape direction reducing the filament coupling losses. Twists with different twist pitches (10-80 mm) were realized in either Ag sheathed and mechanically reinforced AgMg sheathed 37 filament tapes. Possible reasons for the observed degradations of the transport critical current densities of 22000 Acm/sup -2/ (Ag sheath) and 19000 Acm/sup -2/ (AgMg sheath) down to 50% in the worst case (10 mm twist pitch) for twisted tapes, were investigated analyzing the influence of twisting on the conductor geometry and deformation via quantitative image processing of micrographs. The critical current I/sub C/ of differently twisted tapes was measured in a magnetic field for various tape orientations. From the J/sub C/(B) anisotropy the misalignment angle of the Bi(2223) phase texture was analyzed, and a comparison with rocking angles from X-ray experiments was performed.
Keywords :
bismuth compounds; calcium compounds; critical current density (superconductivity); high-temperature superconductors; losses; magnesium alloys; magnetic field effects; multifilamentary superconductors; silver; silver alloys; strontium compounds; superconducting tapes; 10 to 80 mm; AC losses; Bi/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O-Ag; Bi/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O-AgMg; Bi/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x//Ag; Bi/sub 2/Sr/sub 2/Ca/sub 2/Cu/sub 3/O/sub x//AgMg; X-ray experiments; conductor geometry; critical current densities; deformation; filament coupling losses; filament twisting; image processing; magnetic field; misalignment angle; multifilamentary tapes; phase texture; tape orientation; twist pitch; Conductors; Critical current; Critical current density; Current measurement; Degradation; Geometry; Image analysis; Image processing; Magnetic analysis; Magnetic field measurement;
fLanguage :
English
Journal_Title :
Applied Superconductivity, IEEE Transactions on
Publisher :
ieee
ISSN :
1051-8223
Type :
jour
DOI :
10.1109/77.620899
Filename :
620899
Link To Document :
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