Demonstration of an iron-pnictide bulk superconducting magnet capable of trapping over 1 T

Abstract

A trapped field of over 1 T at 5 K and 0.5 T at 20 K has been measured between a stack of magnetized cylinders of bulk polycrystalline Ba0.6K0.4Fe2As2 superconductors 10 mm in diameter and 18 mm in combined thickness. The trapped field showed a low magnetic creep rate (~3% after 24 hours at 5 K), while magneto-optical imaging revealed a trapped field distribution corresponding to uniform macroscopic current loops circulating through the sample. The superconductors were manufactured by hot isostatic pressing of pre-reacted powders using the scalable powder-in-tube technique. A high Vickers hardness of ~3.5 GPa and a reasonable fracture toughness of ~2.35 MPa m0.5 were measured. Given the untextured polycrystalline nature of the cylinders and their large irreversibility field (> 90 T), it is expected that larger bulks could trap fields in excess of 10 T.

11 pages, 5 figures

References in corpus (8)

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Cited by in corpus (14)

• Recent advances in iron-based superconductors toward applications
• Fe-based superconducting thin films on metallic substrates: growth, characteristics and relevant properties
• Grain boundary characteristics of Fe-based superconductors
• High-field transport properties of a P-doped BaFe2As2 film on technical substrate
• Synthesis of CaKFe${}_4$As${}_4$ bulk samples with high critical current density using a spark plasma sintering technique
• Enhanced upper critical field in Co-doped Ba122 superconductors by lattice defect tuning
• Flux trapping in superconducting hydrides under high pressure
• Realization of epitaxial thin films of the superconductor K-doped BaFe${}_{\text{2}}$As${}_{\text{2}}$
• Thermal response of the iron-based Ba122 superconductor to in situ and ex situ processes
• Particulate Generation on Surface of Iron Selenide Films by Air Exposure
• Trapping a magnetic field of 14.8 T using stacked coated conductors of 12 mm width
• Synthesis of $c$-axis textured CaKFe${}_4$As${}_4$ superconducting bulk via spark plasma texturing technique
• Enhancement of the critical current by surface irregularities in Fe-based superconductors
• Observation of Uniform Supercurrent Flow in Polycrystalline K-doped Ba122 by Combined Magneto-optical Imaging and Finite-element Modeling