Investigation of Heat-Treating Conditions for Silver-Sheathed Bi2212 Superconducting Coils

Abstract
Fabrication of silver-sheathed Bi-2212 superconducting coil has been attempted by means of the partial melt growth process. Silver-sheathed Bi-2212 tapes have been cooled down slowly from the temperature range of 875-890°C to 850°C at the rate of 6°C/h. The characteristics of J c-H, AC magnetic susceptibility and X-ray diffraction pattern have been measured, and the SEM image of the cross section has been observed. The pancake-type test coil has been fabricated using an optimized heat-treating condition. This coil generates 0.22 T in the external magnetic field of 0 T and 0.07 T in the external magnetic field of 6.64 T at 4.2 K.