Effect of bending strain on the critical current of Bi-2223/Ag tapes with different structures

We have evaluated the effect of bending strain on the critical current of Bi-2223/Ag tapes with different structures. The measured results were analysed using a symmetric pure bending model. The irreversible degradation indicates that the Ic reduction is caused mainly by crack formation and propagation in the brittle Bi-2223 ceramic core. Experimented results have shown that the number of filaments, as well as the structure of the tapes, could have strong effects on the measured apparent critical values of the tapes. Multifilamentary tapes showed better performance compared with single core tapes. The bending strain tolerance of the tape could be improved by adding a metal strip on the upper side of the tape.