7-filamentary Ba1-xKxFe2As2 (Ba122) iron-based superconductor (IBS) tapes were proven to be applicable to fabricate the high filed insert coils in recent years. The iron-based superconductors with ultrahigh upper critical fields have expected to be used in future high-field applications. However, the current 7-filamentary Ba122 tape is also sensitive to strain. In order to promote the...
The iron-based superconductor is a promising candidate for applications in polycrystalline forms owing to its high current transport performance under high magnetic fields. Especially, doped-BaFe$_2$As$_2$ (Ba122) is particularly interesting in terms of both small anisotropy and small weak-link issues [1]. Epitaxial thin films (ETF) of Ba122-type superconductors have been realized only with Co...
Along with development of hydrogen-use, sustainable society in which it is used as clean energy source as well as energy storage material, MgB2 superconducting power applications have been attracted scientific interest due to its huge potential of superconducting characteristics, made from affordable elements and applicability to liquid hydrogen cooling. As MgB2 wires have been commercially...
MgB2 has been regarded as the most attractive candidate for the next-generation superconducting material due to its high critical temperature and low material cost. Sam Dong Co., Ltd., Korea, is a supplier that produces a variety of the MgB2 superconducting conductors to meet customers’ requirements over the past 6 years. Recently, we have increased the area fraction of...
The iron-based superconductor (IBS) is a good candidate for high field magnet applications. The bending effect and properties of IBS tapes were systematically investigated in this work. The bent Ba1-xKxFe2As2 (Ba122/Ag/AgSn) 7-filamentary tapes with different bending diameters (D=10, 15, 20, 25, 30 mm) were prepared by wind-and-react method. A special mechanical structure was used to prevent...
MgB2 has the highest Tc of 39 K among metallic superconductors [1] and is expected for applications at 10-20 K. MgB2 bulk permanent magnet [2] is interesting for compact, high field magnet applications. Recently, we developed the Magnesium Vapor Transportation (MVT) method [3] that transports magnesium vapor to precursor boron pellets. By using the MVT method, we have succeeded in obtaining...
In previous studies, Jc-strain relation in the reversible range and the irreversible external-tensile strain (ε_irr_t) of MgB2 filament were reported. In general, it is said that ε_irr_t is almost equal to the pre-compressive strain caused by cooling after heat treatment. In this study, the irreversible external-compressive strain (ε_irr_c) of MgB2 multifilament wire was measured. In...
Generally, the wind and react process is used to manufacture MgB2 coil. The react temperature is relatively high, around 650 °C, and this may increase the magnetic field inhomogeneity as a result of the distortion of the winding former. To solve this problem, Kiswire Advanced Technology has developed a twisted cable with fine MgB2 strands that can be wound after heat treatment. In this study,...
