Critical current under magnetic field of Bi/sub 2/Sr/sub 2/Ca/sub 1/Cu/sub 2/O/sub 8+/spl delta///Ag tapes synthesized by electroplating

Bi-2212/Ag tapes have been synthesized by a process, developed with the aim of manufacturing long superconducting lengths at a low economical cost. The technique is based on a sequential electrodeposition of different elements: copper, strontium, bismuth and calcium, on both sides of 50 /spl mu/m thick polycrystalline silver ribbons followed by thermal treatments. A detailed study of the influence of the process parameters on the microstructure has allowed to obtain samples exhibiting very high J/sub c/ values up to 40000 A.cm/sup -2/, in self-field at 77 K. In order to assess the potential applications of the material, we have investigated the behavior of the critical current of our tapes under an external magnetic field at 77 K and at 66 K from transport measurements. The results reported here show that, while decreasing the temperature from 77 K to 66 K, the critical current density increases up to a J/sub c/ (OT, 66 K) value is in excess of 75000. A.cm/sup -2/. Moreover, at 66 K, our tapes are able to sustain supercurrent up to a magnetic field applied parallel to the plane of the tapes equal to 3 T.