High-Tcsuperconducting joints between Ag-clad Bi-2223 tapes have been developed for persistent current applications. Two presintered tapes with one side of the silver stripped were lapped and then wrapped by a silver foil. The complex was uniaxially pressed followed by appropriate sintering to form a high-Tcsuperconducting tape joint. It was found that the ratio of critical currents through the joint to that of the tape,Icj/Ic, depended on the uniaxial pressure and the sintering conduction. At liquid-nitrogen temperature 77 K,Icj/Ic=99 has been achieved. Persistent current loops formed by Bi-2223 tapes have also been fabricated and tested. Joint resistance of a loop was determined to be ∼4×10−13Ω between the decay time of 120 and 360
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