Superconducting joints of Bi-2212/Ag tapes and laminates

Different types of HTS joints of Bi-2212/Ag tapes and laminates, which are fabricated by dip-coating and partial-melt processes, have been investigate d. All joints are prepared using green single and laminated tapes and accor ding to the scheme: coating-joining-pro ces sing. The heat treated tapes ha ve critical current (I-c) between 7 and 27 A, depending on tape thickness a nd the number of Bi-2212 ceramic layers in laminated tapes. It is found tha t the current transport properties of joints depend on the type of laminate , joint configuration and joint treatment. I-c losses in joints of Bi-2212 tapes and laminates are attributed to defects in their structure, such as p ores, secondary phases and misalignment of Bi-2212 grains near the Ag edges . By optimizing joint configuration, current transmission up to 100% is ach ieved for both single tapes and laminated tapes.