Conveners
Wed-Af-Po3.25 - MgB2 and Iron-Based
- Franco Julio Mangiarotti (CERN)
- Kookchae Chung (Korea Institute of Materials Science)
MgB$_{2}$ bulk magnets have been strengthen by the densification, grain refining, and chemical doping. Ti-doped MgB$_{2}$ bulk fabricated by an in-situ hot isostatic pressing (HIP) method also offered the high trapped field, B$_{\rm T}$ of 3.6 T at 13 K [1]. The carbon doping is also well known to bring about the pronounced increase of both the critical current density J$_{\rm c}$ and the...
Hyper Tech Research will report on progress that has been made on developing magnesium diboride superconductor wires, coils and magnets for commercialization efforts, with a specific emphasis on conduction cooled MRI and AC motor/generator applications.
In the drawing process, a non-uniform powder distribution in the MgB2 wire along longitudinal direction can cause degradation of superconducting properties of MgB2 wire and strain hardening of sheath material. It may finally results in breakage of wire due to a stress concentration at locally deformed region in sheath materials. In this study, numerical simulation of drawing process of...
The performance of MgB2 wire (O.D. = 0.67 mm, Length = 8 km) made for a prototype solenoid magnet for X-band (12 GHz) klystron are presented. This solenoid magnet is fabricated by using Wind & React method and is operated as a cryogen-free magnet at 20 K. In this paper, tensile- and bending-stress tolerances of the non-reacted wire and the properties (Ic-B-T, RRR and homogeneity) of the...
In this paper, the km-grade 30-core MgB2 superconducting wire with a diameter of 1.0mm has been prepared by conventional in-situ powder-in-tube method. The metallographic analysis results show that the 30-core MgB2 wire has very good uniformity in both transverse and longitudinal directions, and the critical current (Ic) and critical current density (Jc) reach 95 A and 2.1×105 A/cm2 at 4.2 K...
MgB2 strands have been highly developed commercially, providing great interest in superconducting magnetic energy storage (SMES) applications with low cost by using liquid hydrogen (LH2) as a coolant due to the higher critical temperature compared to the boiling temperature of the LH2. Therefore, the MgB2 SMES is promising device, giving us a remarkable synergy effect by combining the...
In order to reduce the long-term annealing process and prevent excessive grain growth, we attempted to fabricate MgB2 superconducting wires by the rapid heating and quenching (RHQ) method.We have successfully synthesized kilometer-length 6+1 filamentary MgB2 wires reinforced and toughened by Nb/Cu composite with in-situ powder-in-tube method, and for the first time applied the rapidly heating...
Multifilamentary Magnesium diboride (MgB2) wires are composed of brittle compound filaments and metallic sheath with a sufficiently strong reinforced material. A strong reinforced material provides tolerable stress that increases the filament density and enhances the grain connectivity of the MgB2. However, MgB2 wires are highly attractive for various applications due to its high critical...
The Tc of MgB2 superconductors, 39 K, is higher than low temperature superconductors such as NbTi and Nb3Sn, which can allow operating at 20 K by using refrigeration system without the consumption of expensive L-He. In addition to the high Tc, MgB2 has the advantages of longer coherence lengths and the lower anisotropy effect, when compared with the high temperature superconductors, and the...
For the high performance of the wires, cables, and further to the various magnet applications of MgB2 superconducting materials, the important issues have been addressed on the raw precursors of their purity, relative sizes, crystallinity, and the surface conditions including MgO and B2O3 impurities. Since in situ MgB2 superconducting wires have been fabricated using the reaction of Mg and B...
Iron-based superconductors (IBS) are attractive for high-field applications due to the good performances including high upper critical field and low anisotropy. This work describes electro-mechanical properties of the silver-sheathed multifilamentary Ba0.6K0.4Fe2As2 (Ba-122) tape. This tape was fabricated by the ex-situ powder-in-tube (PIT) method and the number of filaments is 7. In order to...
Composite MgB2 wires have been now commercialized by a few industries in the world. In order to use them for applications, it is necessary to evaluate their mechanical property together with critical current and its stress / strain dependence. In the present study, the mechanical properties of three kinds of commercialized MgB2 wires were mainly evaluated. Their observed Young’s moduli...
