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Related papers: Strongly connected ex-situ MgB2 polycrystalline bu…

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MgB2 hollow wires have been produced with a new technique which uses a conventional wire manufacturing process but is applied to composite billets containing the elemental B and Mg precursors in an appropriate shape. The technique has been…

Superconductivity · Physics 2009-11-07 G. Giunchi , S. Ceresara , G. Ripamonti , A. DiZenobio , S. Rossi , S. Chiarelli , M. Spadoni , R. Wesche , P. L. Bruzzone

Among the recently discovered Fe-based superconducting compounds, the (K,Ba)Fe2As2 phase is attracting large interest within the scientific community interested in conductor developments. In fact, after some years of development, critical…

Superconductivity · Physics 2015-09-02 A. Malagoli , E. Wiesenmayer , S. Marchner , D. Johrendt , A. Genovese , M. Putti

We discuss the important aspects of synthesis and crystal growth of MgB2 under high pressure (P) and temperature (T) in Mg-B-N system, including the optimisation of P-T conditions for reproducible crystal growth, the role of liquid phases…

Superconductivity · Physics 2009-11-07 S. Lee , T. Masui , H. Mori , Yu. Eltsev , A. Yamamoto , S. Tajima

Based on DC magnetization measurements, the temperature dependencies of the trapped magnetic field have been calculated for two MgB2 samples prepared by two different techniques: the high-pressure sintering and the hot pressing.…

Superconductivity · Physics 2007-05-23 R. V. Viznichenko , A. A. Kordyuk , G. Fuchs , K. Nenkov , K. -H. Muller , T. A. Prikhna , W. Gawalek

We fabricated (Ba,Na)Fe2As2 superconducting wires using the powder-in-tube method and hot isostatic pressing. By improving powder synthesis processes compared with previous studies, highly pure raw materials for the wire fabrication were…

Superconducting MgB2 thin films were prepared on 50-micrometer-thick, flexible polyamide Kapton-E foils by vacuum co-deposition of Mg and B precursors with nominal thickness of about 100 nm and a special ex-situ rapid annealing process in…

Superconductivity · Physics 2009-11-07 P. Kus , A. Plecenik , L. Satrapinsky , Y. Xu , R. Sobolewski

We report here on a new heat treatment to prepare both dense polycrystalline and single crystal MgB2 high quality samples in one single process. Resistivity measurements for polycrystalline part of the sample gives a residual resistivity…

Superconductivity · Physics 2009-11-07 Mohamed H. Badr , K. -W. Ng

We have developed disk-shaped MgB2 bulk superconducting magnets (20, 30 mm in diameter, 10 mm in thickness) using the in-situ process from Mg and B powders and evaluated the temperature dependence of trapped magnetic field. A pair of two…

Superconductivity · Physics 2012-08-10 A. Yamamoto , A. Ishihara , M. Tomita , J. Shimoyama , K. Kishio

Transport and thermodynamic properties of a sintered pellet of the newly discovered $MgB_2$ superconductor have been measured to determine the characteristic critical magnetic fields and critical current densities. Both resistive transition…

Superconductivity · Physics 2009-11-07 D. K. Finnemore , J. E. Ostenson , S. L. Bud'ko , G. Lapertot , P. C. Canfield

For technical application in windings of coils, transformers or motors, a reinforcement of MgB2 wires and tapes is necessary to withstand applied stresses and strains and to avoid cracks in the filaments. Therefore, the response of the…

The proximity effect in normal/superconductor heterostructures is an intriguing phenomenon in that the normal side takes on the properties of a superconductor with an induced gap. However, the structural and pinning properties of vortices…

In this paper we report a new sol-gel method for the fabrication of MgB2 films. Polycrystalline MgB2 films were prepared by spin-coating a precursor solution of Mg(BH_4)_2 diethyl ether on (001)Al2O3 substrates followed with annealing in Mg…

Superconductivity · Physics 2015-05-27 Liping Chen , Chen Zhang , Yinbo Wang , Yue Wang , Qingrong Feng , Zizhao Gan , Junzhi Yang , Xingguo Li

The high transition temperature and low surface resistance of MgB2 attracts interest in its potential application in superconducting radio frequency accelerating cavities. However, compared to traditional Nb cavities, the viability of MgB2…

Superconductivity · Physics 2013-09-09 Tamin Tai , B. G. Ghamsari , T. Tan , C. G. Zhuang , X. X. Xi , Steven M. Anlage

We present a study of the electrodynamic response of MgB2 pellets and thin film samples exhibiting critical temperatures ranging between 26 and 38 K. We have performed accurate measurements of the surface impedance ZS =RS+iXS as a function…

The critical current density (Jc) of hot isostatic pressed (HIPed) MgB2 wires, measured by d.c. transport and magnetization, is compared with that of similar wires annealed at ambient pressure. The HIPed wires have a higher Jc than the…

We prepared polycrystalline SmFeAsO1-xFx (Sm1111) bulk samples by sintering and hot isostatic pressing (HIP) in order to study the effects of phase purity and relative density on the intergranular current density. Sintered and HIPped Sm1111…

Superconductors with persistent zero-resistance currents serve as permanent magnets for high-field applications requiring a strong and stable magnetic field, such as magnetic resonance imaging (MRI). The recent global helium shortage has…

Superconductivity · Physics 2014-08-07 A. Yamamoto , A. Ishihara , M. Tomita , K. Kishio

Transport current values of 7.5 x 104 A/cm2 at 4.2 K and self-field are reported for MbB2-based tapes. MgB2 strands were formed by directly filling commercially available MgB2 powder into Nb-lined, monel tubes and wire drawing. The wires…

Superconductivity · Physics 2007-05-23 M. D. Sumption , X. Peng , E. Lee , M. Tomsic , E. W. Collings

Here we report a systematic study of superconductive properties of mono-filamentary MgB2-based wires, manufactured with different filling technique. A detailed comparison of the influence of filling technique and final heat treatment on…

Superconductivity · Physics 2014-07-09 Gianmarco Bovone , Davide Nardelli , Davide Matera , Maurizio Vignolo

We report on study of the electronic anisotropy of the newly discovered MgB2 superconductor using the in-plane resistivity measurements in magnetic field applied perpendicular and parallel to Mg and B planes of MgB2 single crystals. The…

Superconductivity · Physics 2009-11-07 Yu. Eltsev , S. Lee , K. Nakao , N. Chikumoto , S. Tajima , N. Koshizuka , M. Murakami