Title :
A new symmetrical arrangement of tape-shaped multifilaments for Bi-2212/Ag round-shaped wire
Author :
Okada, M. ; Tanaka, K. ; Wakuda, T. ; Ohata, K. ; Sato, J. ; Kumakura, H. ; Kiyoshi, T. ; Kitaguchi, H. ; Togano, K. ; Wada, H.
Author_Institution :
Res. Lab., Hitachi Ltd., Ibaraki, Japan
fDate :
6/1/1999 12:00:00 AM
Abstract :
A new Bi-2212/Ag round-shaped wire with tape-shaped multifilaments has been successfully developed. The wire includes 126-960 tape-shaped filaments with triple rotation symmetry, having a good crystal alignment in each filament. We refer to the new wire as ROSATwire, (ROtation-Symmetric Arranged Tape-in-tube wire). Since the ROSATwire structure yields complete symmetrical arrangement of the tape-shaped filaments, it eliminates the need for a rolling machine, but allows us to use a drawing or extrusion machine. We found that the present wire fabrication process markedly improves not only productivity and lowers cost, but also enhances the transport J/sub c/ of the Bi-21212/Ag wire. The I/sub c/ and J/sub c/ reached >340 A and 1000 A/mm/sup 2/ at 28 T and 4 K.
Keywords :
bismuth compounds; calcium compounds; critical current density (superconductivity); high-temperature superconductors; materials preparation; multifilamentary superconductors; silver; strontium compounds; superconducting tapes; 28 T; 4 K; Ag; Bi-2212/Ag round-shaped wire; BiSrCaCuO; HTSC; ROSATwire; cost; critical current density; critical currents; crystal alignment; productivity; symmetrical arrangement; tape-shaped multifilaments; triple rotation symmetry; wire fabrication process; Conductors; Costs; Crystalline materials; Fabrication; Laboratories; Productivity; Shape; Silver; Superconducting films; Wire;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
