HIGH-FIELD SUPERCONDUCTING TAPE MAGNET TECHNOLOGY

The emergence and growth of high-field superconductivity since the 1960's was greatly enhanced by demonstrations in many 10 - 17 T magnets, that Niobium-Tin (Nb3Sn) could be used most reliably in magnets utilizing Nb3Sn in a flexible tape type superconductor form. It was always recognized that if Nb3Sn were readily available in wire or cable form, that might allow design and fabrication of Nb3Sn magnets exhibiting better overall performance, more readily available and comparable to lower field Niobium-Titanium (Nb-Ti) magnets. The discovery of high temperature superconductors (HTS) and resulting efforts to successfully use the newer ceramic oxide materials, such as Bismuth, Yttrium or Thallium based materials, confirms again that, at least in these early developmental stages, fabrication of tape type superconductor configurations are more readily usable towards eventual achievement of more reliably performing high-field magnets. Hence, this paper reviews and discusses methods of magnet design and materials configuration approaches that were found to be most suitable for high current density Nb3Sn high-field tape type magnets. Also discussed are stability, mechanical and thermal design criteria, with a view towards their applicability to the new, higher temperature superconducting materials and high-field magnets.