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Related papers: Strong Pinning Enhancement in MgB2 Using Very Smal…

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Polycrystalline MgB2 samples with 10 wt % silicon powder addition were prepared by an in-situ reaction process. Two different Si powders, one with coarse (44 mm) and the other with nano-size (<100 nm) particles were used for making samples.…

Superconductivity · Physics 2009-11-07 X. L. Wang , S. H. Zhou , M. J. Qin , P. R. Munroe , S. Soltanian , H. K. Liu , S. X. Dou

Doping of MgB2 by nano-SiC and its potential for improvement of flux pinning was studied for MgB2-x(SiC)x/2 with x = 0, 0.2 and 0.3 and a 10wt% nano-SiC doped MgB2 samples. Co-substitution of B by Si and C counterbalanced the effects of…

Superconductivity · Physics 2009-11-07 S. X. Dou , S. Soltanian , J. Horvat , X. L. Wang , P. Munroe , S. H. Zhou , M. Ionescu , H. K. Liu , M. Tomsic

By doping MgB_2 superconductor with SiC nano-particles, we have successfully introduced pinning sites directly into the crystal lattice of MgB_2 grains (intra-grain pinning). It became possible due to the combination of counter-balanced Si…

Superconductivity · Physics 2009-11-07 S. X. Dou , A. V. Pan , S. Zhou , M. Ionescu , H. K. Liu , P. R. Munroe

A series of MgB2 superconducting composite strands co-doped with Dy2O3 and C were prepared via an advanced internal Mg infiltration (AIMI) route.The transport properties and MgB2 layer growth were studied in terms of the Dy2O3 doping level,…

Superconductivity · Physics 2014-09-23 G. Z. Li , M. D. Sumption , M. A. Rindfleisch , C. J. Thong , M. J. Tomsic , E. W. Collings

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…

Superconductivity · Physics 2007-05-23 Chandra Shekhar , Rajiv Giri , R. S. Tiwari , S. K. Malik , O. N. Srivastava

Nanocarbon-doped Fe-sheathed MgB2 tapes with different doping levels were prepared by the in situ powder-in-tube method. Compared to the undoped tapes, Jc for all the C-doped samples was enhanced by more than an order of magnitude in…

Superconductivity · Physics 2009-11-11 Yanwei Ma , Xianping Zhang , G. Nishijima , K. Watanabe , Xuedong Bai

Ex-situ Powder-In-Tube MgB2 tapes prepared with ball-milled, undoped powders showed a strong enhancement of the irreversibility field H*, the upper critical field Hc2 and the critical current density Jc(H) together with the suppression of…

We succeeded in the synthesis of high-Jc MgB2 bulks via high energy ball-milling of elemental Mg and B powder at ambient temperatures. Alternatively to longtime mechanical alloying technique, the mixed powder was ball-milled for only 1h and…

Superconductivity · Physics 2008-01-14 Y. F. Wu , Y. Feng , G. Yan , J. S. Li , H. P. Tang , S. K. Chen , Y. Zhao , M. H. Pu , H. L. Xu , C. S. Li , Y. F. Lu

Highly dense nanocrystalline MgB_2 bulk superconductors with distinctly improved pinning were prepared by mechanical alloying of Mg and B powders and hot compaction at ambient temperatures. The nanocrystalline samples reveal high critical…

Superconductivity · Physics 2009-11-07 A. Gümbel , J. Eckert , G. Fuchs , K. Nenkov , K. -H. Müller , L. Schultz

Bulk samples of MgB2 were prepared with 5, 10, and 15% wt.% Y2O3 nanoparticles added using a simple solid-state reaction route. Transmission electron microscopy (TEM) showed a fine nanostructure consisting of ~3-5 nm YB4 nanoparticles…

We report on significant flux pinning enhancement in MgB2/Fe tapes that has been easily obtained by a simple and cheap route using acetone as both an efficient ball-milling medium and liquid additive through the in situ method. Results…

Superconductivity · Physics 2008-06-27 Dongliang Wang , Yanwei Ma , Zhaoshun Gao , Xianping Zhang , Lei Wang , S. Awaji , K. Watanabe , E. Mossang

Polycrystalline MgB2-xCx samples with x=0.05, 0.1, 0.2, 0.3, 0.4 nano-particle carbon powder were prepared using an in-situ reaction method under well controlled conditions to limit the extent of C substitution. The phases, lattice…

Superconductivity · Physics 2015-06-24 S. Soltanian , J. Horvat , X. L. Wang , P. Munroe , S. X. Dou

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…

Materials Science · Physics 2015-05-13 R. Flukiger , M. S. A. Hossain , C. Senatore

We investigated the effect of SiC nano-particle doping on the crystal lattice structure, critical temperature T_c, critical current density J_c, and flux pinning in MgB_2 superconductor. A series of MgB_{2-x}(SiC)_{x/2} samples with x = 0…

Superconductivity · Physics 2007-05-23 S. X. Dou , A. V. Pan , S. Zhou , M. Ionescu , X. L. Wang , J. Horvat , H. K. Liu , P. R. Munroe

Polycrystalline MgB2 samples with GaN additions were prepared by reaction of Mg, B, and GaN powders. The presence of Ga leads to a low melting eutectic phase which allowed liquid phase sintering and produces plate-like grains. For low-level…

Superconductivity · Physics 2009-11-11 S. K. Chen , Z. Lockman , M. Wei , B. A. Glowacki , J. L. MacManus-Driscoll

A comparative study of pure, SiC, and C doped MgB2 wires has revealed that the SiC doping allowed C substitution and MgB2 formation to take place simultaneously at low temperatures. C substitution enhances Hc2, while the defects, small…

Magnesium diboride (MgB2) powder was mechanically alloyed by high energy ball milling with C to a composition of Mg(B0.95C0.05)2 and then sintered at 1000 C in a hot isostatic press. Milling times varied from 1 minute to 3000 minutes. Full…

Superconductivity · Physics 2009-11-13 B. J. Senkowicz , R. J. Mungall , Y. Zhu , J. Jiang , P. M. Voyles , E. E. Hellstrom , D. C. Larbalestier

Two sets of MgB2 samples doped with up to 5 at. % of Al were prepared in different laboratories using different procedures. Decreases in the a and c lattice parameters were observed with Al doping confirming Al substitution onto the Mg…

Superconducting properties of bulk, dense, pure MgB2 and doped (Mg1-xAx)B2 samples with A = Na, Ca, Cu, Ag, Zn and Al were studied for compositional ranges 0 < x < 0.20. The effect on pinning properties and critical current were…

Superconductivity · Physics 2009-11-07 P. Toulemonde , N. Musolino , R. Flukiger

We have investigated the microstructure, normal-state electrical connectivity, and critical current density of ex-situ MgB2 polycrystalline bulks prepared by systematically varying the sintering conditions under low pressure. Samples heated…

Superconductivity · Physics 2015-06-11 Hiroya Tanaka , Akiyasu Yamamoto , Jun-ichi Shimoyama , Hiraku Ogino , Kohji Kishio
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