Field dependent critical current of Bi-2223/Ag tapes at different thermo-mechanical stages

The critical current of Bi-2223/Ag superconducting samples after the last three thermo-mechanical treatments in the preparation of commercial tapes are measured at 77 K as a function of the magnitude and orientation of an applied field. We show how the zero-field critical current increases and the weak-link dominance is evolved to the strong-link dominance after each treatment. We also study the possibility of scaling the critical current as a function of an effective field, which is calculated from the magnitude and orientation of the applied field assuming a Gaussian distribution of the alignment of the c -axes of superconducting grains.