Damage behavior in Bi-2212 round wire with 3D elastoplastic peridynamic

Bi2Sr2Ca1Cu2O8+x (Bi-2212) wire is the potential material for the design of the high field superconducting magnet. However, compared with excellent current-carrying capacity, low mechanical strength can restrict the wide application of Bi-2212 wire. The superconducting filaments of Bi-2212 wire is sensitive to strain and is prone to fracture, which can lead to the degradation of critical current. Therefore, it is necessary to study the damage behavior of Bi-2212 round wire under external loads. In this paper, the three-dimensional mechanical damage and degradation of critical current in Bi-2212 composite wire under axial tensile load, radial compression load, bending and torsional loads are systematically investigated using ordinary state-based elastoplastic peridynamic (PD). The axial tensile simulations with the process of damage and thermal residual stress are in agreement with the experiment, and the critical current degradation with tensile strain is qualitatively predicted. The effect of plastic deformation of alloy on damage of filament bundles under radial compression load is explored. Finally, the simulations also reveal the damage characteristics of filament bundles in Bi-2212 round wire under torsional and bending loads. The above results are expected to provide a reference for application of Bi-2212 HTS round wire.