Influence of Mechanical Stresses on AC Losses in Multi-Filamentary Bi2223/Ag-Sheathed Wires

Influence of mechanical stresses on AC losses in two kinds of multi-filamentary Bi2223/Ag sheathed wires, twisted and non-twisted, was investigated. The uni-axial tensile stress was applied to the sample wires in liquid nitrogen at atmospheric pressure, and the AC losses (transport, magnetization and total AC losses) were measured by an electric method. The experimental results show that there were differences in the stress dependences of the critical currents which affected the AC loss characteristics. However, the tensile stresses do not influence the AC loss characteristics in both of the two kinds of the samples in reversible critical current region where the stress dependent critical current recovers its virgin value at zero stress by releasing the stresses.