Modeling analysis of distribution of irreversible bending strain for critical current in Bi2223-composite tape

It was attempted to estimate the distribution of irreversible bending strain for critical current of the Bi2223 composite tape. In the modeling, the shape of the core composed of the current transporting Bi2223 filaments and Ag, and the damage strain parameter given by the difference between the intrinsic tensile damage strain and residual strain of the Bi2223 filaments, were incorporated to describe the damage evolution in the core and its relation to critical current. The application of the model to the experimental results of critical current-bending strain relation for many test specimens revealed that the distribution of the irreversible bending strain is described by the two parameter Weibull distribution function. Based on discussion about the influence of the core geometry on the irreversible strain and the result of analysis of the experimental data, a simple and practically useful method was proposed for estimation of the distribution of irreversible bending strain