High Ic superconducting joint between Bi2223 tapes

For realizing high-Tc cuprate superconductors (HTS) magnets equipped with a persistent current circuit, superconducting joints between HTS tapes are indispensable. In the present study, development of superconducting joints with high Ic and high Tc between the Ag-sheathed multi-filamentary Bi2223 commercial tapes were attempted using Bi2223 polycrystalline intermediate joint layers. High joint Ic above 400 A at 4.2 K in the self-field was successfully achieved by the formation of the grain connection between the joint layer and filaments of the tape and by an increase in the number of the joined filaments.