The effects of bending strain on the critical current and alternating loss of Bi2223 HTS tapes

Self-field losses in Bi2223 tapes with different base materials and different number of superconducting filaments were measured at 77K. And the influence of bending strain on critical currents and measured losses were analyzed. The results show that the irreversible strain for silver as the base material is less than 0.15%, and that of Bi2223/Ag-Mn is more than 0.3%. The deterioration of the critical current due to the strain originates from the micro-crack along the cross section of the superconducting core. Increasing the number of filaments and alloy base materials can improve its mechanical properties. The deterioration of critical current caused by bending strain leads to an increase in alternating losses.