Three-dimensional multifilament finite element models of Bi-2212 high-temperature superconducting round wire under axial load

Abstract

We established a three-dimensional (3D) multifilament finite element model for Bi-2212 round wire under axial load and analyzed its mechanical behavior. The model considered the initial thermal residual stress and damage of Bi-2212 superconducting filaments. The proposed model accurately predicted the axial mechanical behavior of strands. In addition, the characteristics of hysteresis loops in the stress–strain curves of Bi-2212 high-temperature superconducting (HTS) round wire under axial cyclic load were also obtained, agreeing well with experimental data. We constructed a 3D multifilament finite element model and 3D homogenized finite element model of a Bi-2212 HTS triplet. Both the results predicted by multifilament finite element model and homogenized model are close to the experimental data. The former gave more accurate stress distribution characteristics of strands than the latter. However, the homogenized model maybe more suitable for modeling of higher-level cables than the triplet model because of its lower computational cost.