Mechanical properties of jointed Bi-2223/Ag tapes

We investigated the mechanical properties of a superconducting a joint of 37-filament Bi-2223/Ag tapes. The tensile strain tolerance characteristics of the tapes was observed and compared with the characteristics of normal ones, Even though the jointed tapes were strengthened by silver foil, the degradation of their critical current occurred before normal ones. The fatigue properties of the tapes, when strain was applied repeatedly, was evaluated, The critical strain was less than the elastic strain of the tapes. The critical current of jointed tapes decreased earlier than normal ones at the tests. This may be caused by defects of the core where two tapes were overlapped. The strength of the core is more important than of the sheath to improve the mechanical properties of the tapes, (C) 2002 Elsevier Science B.V. All drights reserved.