Mechanical properties and their influence to transport property of multifilamentary Bi2223 tape

In order to investigate mechano-electromagnetic property, a structure model is proposed based on the rule of mixture. A comparison with experiments made clear that the present tapes show a three stage behavior. The first elastic region (stage I') is very narrow and followed by stage II', where the slope of stress - elongation curve decreased gradually. Then the macroscopic yield and the plastic deformation region (stage III) appeared. A discernible degradation of critical current was observed at stages I' and II'. This degradation is nearly reversible and vanishes when the external tensile load was reduced to zero. At stage III, the critical current decreased abruptly and largely due to generation of macroscopic cracks.