Mechanical stress in high-temperature superconducting ring-shaped bulk during the pulsed-field magnetization

The high-temperature superconducting(HTS)bulk has a higher critical current density and can trap the larger magnetic field.When the high-temperature superconducting bulk is magnetized by the pulsed-field,it will be subjected to electromagnetic stress and thermal stress.Furthermore,the bulk may be damaged under larger mechanical stress or strain during the pulsed-field magnetization.In this paper,the electromagnetic field,the temperature and the mechanical response of the ring-shaped bulk are simulated based on the electromagnetic and mechanical governing equations,and the simulated trapped field is consistent with the experimental results given in the reference.The stress distribution on the top surface of the ring-shaped bulk during pulsedfield magnetization is opposite to the case of field cold magnetization.Moreover,the inner edge on the middle plane of the bulk may be broken more easily than the outer edge during the pulsed-field magnetization.Afterward,the influences of the size of the inner radius,ambient temperature and rise time of the applied field are presented.Finally,the mechanical stress of the bulk with the cooling process is investigated,and the tensile stress on the surface can be enhanced by the cooling process.