Effects of Spatial Distribution of Defects on Bending Deformation and Critical Current in Bi2223/Ag Superconducting Composite Tapes
The strain dependence of the critical current, Ic, of Bi2223/Ag/Ag-alloy composite superconducting tapes has been studied both experimentally and analytically under bending deformation for two types of tape used in the VAMAS bending round-robin program (classified as VAM1 and 3). Our former analysis showed that the experimentally obtained Ic values were between the calculated ones based on a damage-free initial state and a case where delamination occupied the full width of the tape mid-plane. The experimentally obtained Ic values were explained by the delamination occupying partial width of the tape mid-plane. However, the microscopic observation indicated that the delamination location in the thickness direction was not limited to the mid-plane. In the present study, the analysis was modified to incorporate the movement of the delamination location in the thickness direction. The calculated Ic values with delamination increased when the delamination location moved to compressive side of the tape, and decreased when that moved to tensile side of the tape. Finally, the experimental Ic values can be understood by the distribution of delamination in both width and thickness direction.
T. Chandra, K. Tsuzaki, M. Militzer , C. Ravindran
M. Hojo et al., "Effects of Spatial Distribution of Defects on Bending Deformation and Critical Current in Bi2223/Ag Superconducting Composite Tapes", Materials Science Forum, Vols. 539-543, pp. 919-924, 2007