Superconductive joint on Bi2223/Ag multifilamentary tape

The joining methods between two Bi2223/Ag powder-in-tube–multifilamentary tapes were investigated in this paper. Several kinds of joining process––lap, butt and direct joint were used for green and reacted Bi-tapes. The experimental results and analyses of different methods show that the biggest critical current ratio (CCR) could be obtained by direct connection on green tapes. Meanwhile, on reacted tapes, the biggest CCR (about 77%) was also gained by direct connection with precursor powder adopted 10% Ag. It was found that the sinter time of jointed tape for retaining the better critical current should be shorter than that of unjoined (original) tapes. The critical current versus sinter time curve of jointed tape is much difference comparing with original tape. The microstructure and properties of jointed tape were studied.