Dynamics of magnetic flux propagation in bulk, single grain superconducting rings during pulsed field magnetisation

Abstract When used as trapped field magnets (TFMs), single grain, bulk high-temperature superconducting (HTS) rings are promising candidates for the generation of strong, uniform magnetic fields nuclear resonance. The pulsed magnetisation (PFM) technique provides a low cost, compact and portable method to magnetise these samples TFMs; however it has proven difficult achieve high in HTS using PFM. To date, record only 0.60 T been achieved magnetised by single-pulse PFM—compared with over 4 disc-shaped HTS—and reasons this discrepancy poorly understood. In work, we use finite element model propagation flux into under quasi-static zero cooled PFM, validate results analytically experimentally. Magnetic is found penetrate from both inner outer surfaces, inducing negative at face ring. This reversed applied increases past point full penetration, locally dissipating energy heating sample. therefore more susceptible local instabilities that severely limit their ability trap useful field. Consequently, thermomagnetic stability during PFM can be ensured taking careful consideration reducing movement through around which reversed. may require advanced techniques like waveform control or multi-pulse stepwise-cooling reduce increase