Related papers: Supercurrents in Magnesium Diboride/Metal Composit…
The effect of high magnetic fields on the current carrying properties of both MgB2 bulks and Fe-sheathed tapes was investigated following different thermal sequences. It is found that application of a large magnetic field during processing…
Monofilamentary MgB2-wires with a 2- or 3-component sheath containing mechanical reinforcing stainless steel (SS) were prepared and characterized. In direct contact to the superconductor Nb, Ta or Fe was used. For a selection of samples…
We demonstrate a large enhancement of critical current density (Jc) up to 1.0x10^7 A/cm2 at 5 K under self-field in (Ba,K)Fe2As2 single crystals by irradiating 320 MeV Au ions. With the very promising potential of this material in mind, we…
Multifilamentary MgB2/Fe wires and tapes with high transport critical current densities have been fabricated using a straightforward powder-in-tube (PIT) process. After annealing, we measured transport jc values up to 1.1 * 105 A/cm2 at 4.2…
From the application point of view, large critical current densities Jc (H) for superconducting wires are required, preferably for magnetic fields higher than 5 T. Here we show that strong c-axis textured Sr1-xKxFe2As2 tapes with nearly…
A series of doping experiments are reported for MgB2 conductors that have been synthesized using doped boron fibers prepared by chemical vapor deposition(CVD) methods. Undoped MgB2 samples prepared from CVD prepared fibers consistently give…
The powder-in-tube MgB2 wires were prepared by high energy milling of Mg and B powder. The powder was not mechanically alloyed for 2h short milling time. However, the MgB2 grains in wires are very small (20 100nm) and resembled to the…
Seven years after the discovery of superconductivity in magnesium diboride, the fundamental superconducting properties of this compound are well known and the peculiar current transport in polycrystalline materials is essentially…
We found that transport critical current density (Jc) of the Ba1-xKxFe2As2/Ag tapes is significantly enhanced by the combination process of cold flat rolling and uniaxial pressing. At 4.2 K, the Jc reaches a high value of 9.1x104 A/cm2 in 4…
We report dc transport and magnetization measurements of Jc in MgB2 wires fabricated by the powder-in-tube method, using commercial MgB2 powder with 5 %at Mg powder added as an additional source of magnesium, and stainless steel as sheath…
The new class of Mg-B superconducting conductors was prepared using the standard in-situ powder-in-tube, PIT, method where Mg+2B mixture was used to fill the copper and silver tubes. Study of the intergranular current, grain connectivity…
Superconducting Ag or Cu sheathed MgB2 wires have been fabricated by conventional powder-in-tube techniques. The in-situ reaction of Mg and B powders with atomic proportions of 1:2 and 1.33:2 inside Ag or Cu tubes at low temperatures have…
The transport of electrical current through a superconductor falls into three broad regimes: non-dissipative, dissipative but superconducting, and normal or non-superconducting. These regimes are demarkated by two definitions of critical…
In the present investigation, we report a systematic study of Ag admixing in MgB2 prepared by solid-state reaction at ambient pressure. All the samples in the present investigation have been subjected to structural/ microstructural…
We succeeded in the fabrication of high-Jc MgB2/Fe wires applying the internal Mg diffusion (IMD) process with pure Mg core and SiC addition. A pure Mg rod with 2 mm diameter was placed at the center of a Fe tube, and the space between Mg…
The diboride materials MB2 (M = Mg, Be, Pb, etc.) are discussed on the basis of the 3D Josephson junction array (JJA) model due to Kawabata-Shenoy-Bishop, in terms of the B-B layers in the diborides analogous to the Cu-O ones in the…
We have fabricated a series of iron-sheathed superconducting wires prepared by the powder-in-tube technique from (MgB_2)_{1-x}:(Mg+2B)_x initial powder mixtures taken with different proportions, so that x varies from 0 to 1. It turned out…
The high upper critical field and low anisotropy of iron-based superconductors make them being particularly attractive for high-field applications. However, the current carrying capability needs to be enhanced by overcoming the weak-link…
In high-quality c-axis-oriented MgB2 thin films, we observed high critical current densities (Jc) of 16 MA/cm^2 at 15 K under self fields comparable to those of cuprate high-temperature superconductors. The extrapolated value of Jc at 5 K…
Cold high pressure densification (CHPD) is presented as a new way to substantially enhance the critical current density of in situ MgB2 wires at 4.2 and 20 K at fields between 5 and 14 T. The results on two binary MgB2 wires and an alloyed…