@@New (Nb,Ta)3Sn conductors
with attractive high-field performance have been fabricated from
Ta-Sn/Nb(Nb-Ta) composites. A thick and uniform (Nb,Ta)3Sn
layer is formed at the interface between the Ta-Sn core and the
Nb(Nb-Ta) sheath. When the Ta concentration exceeds 40at%, the
Ta-Sn ingot can be crushed into a fine powder and then the powder
core process is applied to fabricate the composites. Meanwhile,
when the Ta concentration is below 30at%, a ductile Ta-Sn sheet
can be prepared and then the Jelly Roll process is applied to
fabricate the composites as illustrated in the figure. A non-Cu
Jc of 15,000A/cm2 is achieved at 22`23T and 4.2K in both
the powder core and the Jelly Roll processed wires after an appropriate
heat treatment.
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Faculty of Engineering,
Tokai University : |
Kyoji Tachikawa, Makoto Aodai,
Hiroyuki Izawa |
IMR, Tohoku University : Kazuo
Watanabe |
Reference : |
K.Tachikawa, T. Kato, H. Matsumoto, R.
Kato, T. Takeuchi
"High-field performance and structure of (Nb,Ta)3Sn
superconductors produced by Ta-Sn core",
IEEE Trans. Appl. Supercond. 11 (2001) 3663-3666. |
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