Rotating magnetization method for inspection of local defect in HTS conductor

Abstract

Abstract High temperature superconducting (HTS) magnet used for a accelerator for high energy physics or a large-scale magnetic confinement system for nuclear fusion requires large current capacity HTS conductor in order to dump the stored magnetic energy quickly to protect the coil when quench has been occurred. To realize the HTS conductor, superimposed or stacked HTS tapes conductors are invented. However, local degradation of the critical current has been observed in the production of HTS conductors. Therefore, to confirm the soundness of the HTS conductor, it is necessary to establish the non-destructive detection method for the observation of degraded HTS tapes. In this study, we have investigated to inspect the degradation position in stacked HTS tapes by adopting rotating magnetization measurement method. This measurement method is measuring magnetization signal by rotating and transporting stacked HTS tapes in a static magnetic field. As a result, intentionally introduced buckling defect positions were detected by this measurement method.