High transport critical current density obtained for powder-in-tube-processed MgB2 tapes and wires using stainless steel and Cu–Ni tubes

  title={High transport critical current density obtained for powder-in-tube-processed MgB2 tapes and wires using stainless steel and Cu–Ni tubes},
  author={Hiroaki Kumakura and Akiyoshi Matsumoto and Hiroki Fujii and K. Togano},
  journal={Applied Physics Letters},
MgB2 tapes and wires were fabricated by the powder-in-tube method. Stainless steel and Cu–Ni tubes were used as sheath materials, and no heat treatment was applied. The tapes made of stainless steel showed transport critical current density Jc of about 10 000 A/cm2 at 4.2 K and 5 T. A high Jc of about 300 000 A/cm2 was obtained by extrapolating the Jc–B curves to zero field. Multifilamentary (seven-core) MgB2 wire was successfully fabricated using Cu–Ni tubes. For both tapes and wires, the… 
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