Bend strain and tensile stress characteristics of (Bi, Pb)-2223/Ag-Cu alloy sheathed tapes

The dependence of I-c on the bend strain and tensile stress characteristics of (Bi, Pb)-2223/Ag-Cu alloy sheathed tapes with varying Cu composition in the sheath has been studied in both mono- and multifilamentary configurations. The irreversible stain (epsilon (r)) and the critical stress (sigma (c)) were found to improve as the level of Cu doping in the sheath increases. epsilon (r) and sigma (c) were found to be about twice as large for the 9 at% Cu doped sample in both mono- and multifilamentary cases compared to the corresponding pure samples. The multifilamentary tapes were found to endure more strains and stresses due to their fine filament structure and low fill factor of the superconductor core. The degradation of I-c above sigma (c) was found to be rapid, while that for strains above epsilon (r) was gradual, retaining a significant amount of I-c even after high values of applied strain.