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Related papers: Superconducting Properties of Highly Dense MgB2 Bu…

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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

The structural properties of MgB2 superconductors have been analyzed by means of convergent-beam electron diffraction, high-resolution transmission-electron microscopy, and theoretical simulations. The MgB2 crystal has been identified to…

Superconductivity · Physics 2007-05-23 J. Q. Li , L. Li , Y. Q. Zhou , Z. A. Ren , G. C. Che , Z. X. Zhao

We report on the results of a comparative investigation of highly dense bulk MgB$_2$ samples prepared by three methods: (i) hot deformation; (ii) high pressure sintering; and (iii) mechanical alloying of Mg and B powders with subsequent hot…

We synthesized single crystalline and policrystalline MgB_2 under ambient pressures. The single crystals of MgB_2 were of good quality, where the crystal structure refinements were successfully converged with R = 0.020. The specific heat of…

Superconductivity · Physics 2009-11-07 Y. Machida , S. Sasaki , H. Fujii , M. Furuyama , I. Kakeya , K. Kadowaki

MgB2 thick film was synthesized on the stainless steel substrate by the technique of hybrid physical-chemical vapor deposition (HPCVD), using Mg ingot and B2H6 as the raw materials. The film thickness is about 10 microns. The scanning…

Superconductivity · Physics 2015-06-24 Qing-rong Feng , Chinping Chen , Ying Lu , Zhang Zia , Jing-pu Guo , Xiao-nan Wang , Meng Zhu , Jun Xu , Yong-zhong Wang

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

In this letter, we report the first successful fabrication of dense, metal-clad MgB2 superconductor wires as well as the first demonstration of high transport Jc of greater than 36,000 A/cm2 in MgB2. The fabrication technique that we…

Superconductivity · Physics 2007-05-23 S. Jin , H. Mavoori , R. B. van Dover

Dense pure and doped (Mg1-xAx)B2 samples with A = Na, Ca, Cu, Ag, Zn and Al were synthesized at high pressure - high temperature in a multi anvils press (3.5-6 GPa, 900-1000C) for x up to 0.20. They were studied by x-ray diffraction,…

Superconductivity · Physics 2007-05-23 P. Toulemonde , N. Musolino , H. L. Suo , R. Flukiger

The discovery of superconductivity at 39 K in magnesium diboride offers the possibility of a new class of low-cost, high-performance superconducting materials for magnets and electronic applications. With twice the critical temperature of…

The synthesis of MgB2-based materials under high pressure gave the possibility to suppress the evaporation of magnesium and to obtain near theoretically dense nanograined structures with high superconducting, thermal conducting, and…

In this paper, we reported the structural properties and superconductivity of Mg(B1-xCx)2 compounds. Powder x-ray diffraction results indicate that the samples crystallize in a hexagonal AlB2-type structure. Due to the chemical activity of…

Materials Science · Physics 2009-11-07 Shao-ying Zhang , Jian Zhang , Tong-yun Zhao , Chuan-bing Rong , Bao-gen Shen , Zhao-hua Cheng

The normal state and superconducting properties of MgB2 and Mg1-xAlxB2 are discussed based on structural, transport, and high pressure experiments. The positive Seebeck coefficient and its linear temperature dependence for Tc<T<160 K…

Superconductivity · Physics 2007-05-23 B. Lorenz , Y. Y. Xue , R. L. Meng , C. W. Chu

Bulk textured MgB_2 material of nearly full density showing a weak c-axis alignment of the hexagonal MgB_2 grains parallel to the pressure direction was obtained by hot deformation of a stoichiometric MgB_2 pellet prepared by a gas-solid…

Superconductivity · Physics 2007-05-23 A. Handstein , D. Hinz , G. Fuchs , K. -H. Müller , K. Nenkov , O. Gutfleisch , V. N. Narozhnyi , L. Schultz

We have determined the structural properties of the superconducting compound MgB2 as a function of temperature from 11 K to 297 K and as a function of hydrostatic pressure up to 0.62 GPa using neutron powder diffraction. This compound, when…

Superconductivity · Physics 2009-11-07 J. D. Jorgensen , D. G. Hinks , S. Short

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 the effect of the sintering temperature on the superconductivity of MgB2 pellets prepared under a high pressure of 3 GPa. The superconducting properties of the non-heated MgB2 in this high pressure were poor. However, as the…

Superconductivity · Physics 2009-11-07 C. U. Jung , Min-Seok Park , W. N. Kang , Mun-Seog Kim , Kijoon H. P. Kim , S. Y. Lee , Sung-Ik Lee

The upper critical field Hc2(T) of sintered pellets of the recently discovered MgB_2 superconductor was investigated by transport, ac susceptibility and dc magnetization measurements in magnetic fields up to 16 T covering a temperature…

Superconductivity · Physics 2009-11-07 G. Fuchs , K. -H. Müller , A. Handstein , K. Nenkov , V. N. Narozhnyi , D. Eckert , M. Wolf , L. Schultz

$MgB_2$ becomes superconducting just below 40 K. Whereas porous polycrystalline samples of $MgB_2$ can be synthesized from boron powders, in this letter we demonstrate that dense wires of $MgB_2$ can be prepared by exposing boron filaments…

The paper reports the first successful fabrication of MgB2 superconducting tape using a flexible metallic substrate as well as its strong pinning force, which was verified by direct measurement of transport critical current density. The…

Superconductivity · Physics 2009-11-07 K. Komori , K. Kawagishi , Y. Takano , H. Fujii , S. Arisawa , H. Kumakura , M. Fukutomi , K. Togano

We have studied the structural and superconducting properties of MgB$_2$ thin films made by pulsed laser deposition followed by in situ annealing. The cross-sectional transmission electron microscopy reveals a nanocrystalline mixture of…