Influence of iridium doping in MgB2 superconducting wires

Abstract

Document Version Peer reviewed versionLink back to DTU Orbit Citation (APA): Grivel, J-C. (2018). Influence of iridium doping in MgB2 superconducting wires. Physica C: Superconductivity and its Applications, 547, 7-15. https://doi. Highlights MgB 2 wires doped with Ir (iridium) were prepared and reacted in Ar.  The solubility limit of Ir in the MgB 2 lattice is not larger than 1.5 at.% relative to Mg.  The critical current density is degraded in the Ir-doped samples. AbstractMgB 2 wires with iridium doping were manufactured using the in-situ technique in a composite Cu-Nb sheath. Reaction was performed at 700°C, 800°C or 900°C for 1h in argon atmosphere. A maximum of about 1.5 at.% Ir replaces Mg in MgB 2. The superconducting transition temperature is slightly lowered by Ir doping. The formation of IrMg 3 and IrMg 4 secondary phase particles is evidenced, especially for a nominal stoichiometry with 2.0 at.% Ir doping. The critical current density and accommodation field of the wires are strongly dependent on the Ir content and are generally weakened in the presence of Ir, although the effect is less pronounced at lower temperatures.

Increase of the critical current density of MgB2 superconducting bulk samples by means of methylene blue dye additions

“…Carbon doping on the boron sites in the MgB2 crystal lattice is also known to be effective in enhancing the pinning force and hence the jc of MgB2 under high magnetic fields [12][13][14][15][16][17][18][19][20]. This is in contrast to the general tendency resulting from foreign element doping on the Mg sites [21][22][23][24][25][26], as well as of Al doping on the B sites [27][28][29][30][31], which induce adverse effects or only limited improvements of the jc(B) performance due to the influence of these elements on various parameters.…”

Extreme Learning Machine Approach to Modeling the Superconducting Critical Temperature of Doped MgB2 Superconductor

“…The measured superconducting critical temperature, room temperature resistivity (RTR), crystal lattice parameters (LP) of doped MgB 2 superconductor and residual resistivity ratio (RRR) employed in developing the SINE-ELM-RTR model, SINE-ELM-LP model and SIG-ELM-RRR model were obtained from the literature [1][2][3][10][11][12][13]15,. While the presence of dopants in MgB 2 superconductor results in distortion, with which the developed SINE-ELM-LP model estimates the superconducting critical temperature, RTR and RRR measure the degree of disorder and impurity scattering resulting from the introduced dopants.…”

“…Discovery of superconductivity behavior in magnesium diboride (MgB 2 ) widened the potentials of the material for superconductor applications, such as liquid-helium-free magnetic resonance imaging systems, generators, transformers and fault current limiters, among others [1][2][3][4]. Apart from the fact that MgB 2 is a compound made from two relatively cheap, light elements, the abundance of these elements is another significant factor that enhances its fabrication at a very low cost [5].…”

Development of Magnesium Diboride Superconducting Wires through Hot Working with Different Initial Filling Density

“…Magnesium diboride, MgB2, is a novel high critical temperature superconductor with a critical temperature of 39 K, initially introduced in the early twenty -first century (Nagamatsu et al, 2001). The versatility of MgB2 also extends to its production in various forms and shapes, including bulk (Arvapalli et al, 2021;Zhang et al, 2020;Zheng et al, 2019), thin films, tapes, and wires (Balog et al, 2018;Grivel, 2018b;Herbirowo et al, 2018;Kováč et al, 2011;Vinod et al, 2009). Consequently, this material has found promising applications in various electronic devices due to its excellent electrical contact between grains and cost-effectiveness.…”