The Effectiveness of Pulsed-Field Magnetization with Respect to Different Performance Bulk Superconductors

Pulsed-field magnetization (PFM) is one of the practical activation techniques for bulk applications, especially as an inexpensive, small-volume, and mobile experimental setup. To utilize the method, its effectiveness to excite the bulk superconductors was examined by four samples with different trapped-flux performance as representatives. The PFM experiments were conducted with a pair of vortex-type copper coils at liquid nitrogen temperature (77 K). The utmost trapped-flux performance of the four samples was obtained by a multi-PFM method with progressively increased applied fields. By comparison with their trapped-flux results of static field-cooling magnetization (FCM), the effectiveness of PFM according to different performance bulk superconductors was analyzed. It was found that with the improvement of the bulk performance, the PFM results start to deviate from the FCM ones more and more, indicating a harder tendency to excite the bulk samples by the PFM method. The possible explanations from heat generation during the pulse and some suggestions to the improvement of the PFM process for practical applications are discussed.