Relation of Constituents with Superconducting Characteristics in Low-Temperature-Preheated YBCO Ceramics

1992 ◽  
Vol 275 ◽  
Author(s):  
Junya Nishino ◽  
Hiroaki Nishikawa ◽  
Muneo Ayabe ◽  
Yuji Ikegami
Keyword(s):  
Critical Temperature ◽  
Low Temperature ◽  
Critical Current Density ◽  
Superconducting Properties ◽  
Ybco Bulk ◽  
Disordered Phase ◽  
Yttrium Barium ◽  
Ybco Ceramics ◽  
Critical Current Density Jc ◽  
Critical Temperature Tc

ABSTRACTYBCO bulk ceramics pre-heated at low temperature before sintering were studied on the structure and superconducting properties mainly by varying the concentration of Ba/Y ratio.At 15.8–16.2wt% of the oxygen content Oc calcurated from the compositions of yttrium, barium and copper on the assumption that the valence of copper is 2, (123) phase is main and critical temperature(Tc) and critical current density(Jc) reach to 88–90K and about 103A/cm2, respectively.It is presumed that there is a possibility of the exixtence of oxygen deficient and disordered phase in addition to (123) and (211) phases and BaCuO2.

YBCO Bulk Superconductors with Sm Addition

2017 ◽  
Vol 891 ◽  
pp. 483-488 ◽  
Author(s):  
Daniela Volochová ◽  
Vitaliy Antal ◽  
Jozef Kováč ◽  
Pavel Diko
Keyword(s):  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Superconducting Properties ◽  
Ybco Bulk ◽  
Pinning Centers ◽  
Bulk Superconductors ◽  
Powder Addition ◽  
Current Densities ◽  
Precursor Powders

The influence of Sm addition on the microstructure and superconducting properties of Y-Ba-Cu-O (YBCO) bulk superconductors has been studied. Precursor powders YBa2Cu3O7-δ (Y-123), Y2O3 and CeO2 were enriched with different amounts of SmBa2Cu3Oy (Sm-123) or Sm2O3 powders with the aim to increase critical current density, Jc,by introducing additional pinning centers. YBCO bulk superconductors with SmBa2Cu3Oy (Y123-Sm) or Sm2O3 (Y123-SmO) powder addition were prepared by the optimized top seeded melt growth process in the form of single grains. Microstructure analysis revealed that Sm2O3 addition leads to a higher amount of smaller Y2BaCuO5 (Y-211) particles, what is related to high critical current densities (Jc ~ 7 x 104 A/cm2) of the YBCO samples with Sm2O3 addition in low magnetic fields. The effect of Sm addition in the form of SmBa2Cu3Oy as well as Sm2O3 powder on Y2BaCuO5 particle size, critical temperature, Tc, and critical current density, Jc, is reported.

Porosity Effect on Superconducting Properties of YBa2Cu3Oδ and YCaBa4Cu6Oδ

2015 ◽  
Vol 1107 ◽  
pp. 601-605
Author(s):  
S.A. Senawi ◽  
H. Azhan ◽  
W.N.F.W. Zainal ◽  
W.A.W. Razali ◽  
A. Nazree ◽  
...  
Keyword(s):  
Critical Temperature ◽  
Critical Current Density ◽  
Porous Structure ◽  
Critical Current ◽  
Current Density ◽  
Resistivity Measurement ◽  
Effective Cross Section ◽  
Ceramic Materials ◽  
Solid State Reaction Method ◽  
Superconducting Properties

This paper reports on the properties of YBa2Cu3Od (Y123) and YCaBa4Cu6Oy (Y146) with non-porous and porous structures. The relationship between calcium doping and critical temperature (Tc) was studied to determine the optimal superconducting properties. A series of heating and grinding via solid state reaction method was used to fabricate the ceramic materials. The electrical properties were investigated via critical temperature, TC and critical current density, JC using the resistivity measurement system (RMS). Scanning Electron Microscope (SEM) and X-Ray Diffraction (XRD) were used to analyze the material morphology and structure, respectively. The orthorhombicity increased due to less porosity of the samples. The calcium presence partially replaced larger Ba(II) site and degraded orthorhombicity. The highest critical current density (JC) was porous YCaBa2Cu3Oy which was 2.32 A/cm2 compared to 0.75 A/cm2 for porous YCaBa4Cu6Oy at 60 K. The critical temperature for porous structure was less than non porous structure for Ca doped Y146 system which was 69.9 K and 67.9 K. SEM micrograph unveiled that the Jc was induced significantly by continuity of grain formation via grain size. Pores homogenized the grains surface quality and connectivity due to strain release thus increasing effective cross section of the sample for current density (Jc) over the vast areas.

Fabrication and Superconducting Properties of High Tc Oxide Wire

1987 ◽  
Vol 99 ◽  
Author(s):  
N. Sadakata ◽  
Y. Ikeno ◽  
M. Nakagawa ◽  
K. Gotoh ◽  
O. Kohno
Keyword(s):  
Critical Current Density ◽  
Liquid Nitrogen ◽  
Liquid Nitrogen Temperature ◽  
Intrinsic Properties ◽  
Superconducting Properties ◽  
Intensive Study ◽  
High Tc ◽  
Fabrication Procedure ◽  
Paper Fabrication ◽  
Critical Current Density Jc

Since the discovery of high Tc superconducting oxide such as Ln-Ba-Cu-O system which shows superconductivity above liquid nitrogen temperature, intensive study has been carried out to investigate its intrinsic properties[l-4]. Superconducting wire which operates in liquid nitrogen is one of the emerging products among application, however, there are many factors to be investigated for practical use. Critical current density, Jc, is one of the most important characteristics of superconductor, although, only few report describing Jc measurement ever published[5]. In this paper, fabrication procedure of silver sheathed Y-Ba-Cu-O wire by powder metallurgical technique and its superconducting properties have been reported. Other factors which may influence superconductivity such as microstructure of the oxide, configuration of wires, etc. are also discussed.

Enhanced Transport Current in MgB2 Superconducting Wire through Metallic Fe Addition

2015 ◽  
Vol 830-831 ◽  
pp. 509-512
Author(s):  
Neson Varghese ◽  
Devadas Kavazhikath Mohandas ◽  
Aswathy Pillai Mohan ◽  
Anooja Jayakumari Babu ◽  
Manoj Raama Varma ◽  
...  
Keyword(s):  
Low Temperature ◽  
Critical Current Density ◽  
Flux Pinning ◽  
Transport Current ◽  
Transport Critical Current Density ◽  
Superconducting Properties ◽  
Superconducting Wires ◽  
Fe Content ◽  
Composite Wires ◽  
Fe Addition

The structural and superconducting properties of iron sheathed mono-filamentary superconducting wires of MgB2 with and without Fe addition processed at a relatively low temperature of 600 °C were investigated. The transport critical current density (JC) of the superconducting composite wires is found to increase steadily with an increase in Fe content to an optimum of 10 wt.% is reached. The magnetic JC and flux pinning analysis of the samples carried out up to a field of 9 T also show significant enhancements throughout the entire field of study. Another observation is that the TC of the composites doesn’t vary much, indicating that the added Fe has not gone in to the MgB2 lattice.

scholarly journals Effect of Pressure on the Superconducting Properties of Tl2Ba2Ca2Cu3O9-δ

Crystals ◽  
2018 ◽  
Vol 9 (1) ◽  
pp. 4
Author(s):  
Anota Ijaduola ◽  
Rai Shipra ◽  
Athena Sefat
Keyword(s):  
Transition Temperature ◽  
Hydrostatic Pressure ◽  
Critical Current Density ◽  
Current Density ◽  
Magnetic Hysteresis ◽  
Superconducting Transition ◽  
Superconducting Properties ◽  
Piston Cylinder ◽  
State Formula ◽  
Critical Current Density Jc

This study investigated the application of pressure on the superconducting properties of a thallium-based cuprate, namely Tl2Ba2Ca2Cu3O9-δ (Tl-2223). The superconducting transition temperature (Tc) and the critical current density (Jc) were studied by applying ~1 GPa of pressure. This hydrostatic pressure was applied in a piston-cylinder-cell (PCC), using Pb as a manometer and Daphne 7373 oil as the pressure transmitting medium. For estimating the Jc, we used Bean’s critical state formula on the magnetic hysteresis curves at 10 K and 20 K. Both the Tc and Jc improved with pressure. The Jc values increased at both temperatures and the Tc value increased by 4 K with a pressure of 0.8 GPa. These results clearly indicate that pressure is another tool to control properties of quantum materials.

scholarly journals О возможности изготовления мостиков YBCO с совершенной поверхностью, критической температурой более 88 K и плотностью критического тока до 5·10-=SUP=-6-=/SUP=- A/cm-=SUP=-2-=/SUP=-

2020 ◽  
Vol 62 (9) ◽  
pp. 1398
Author(s):  
Д.В. Мастеров ◽  
С.А. Павлов ◽  
А.Е. Парафин ◽  
Е.В. Скороходов
Keyword(s):  
Critical Temperature ◽  
Surface Morphology ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Growth Process ◽  
Ybco Films ◽  
Basic Parameters ◽  
Critical Current Density Jc ◽  
Electrophysical Parameters

In the fabrication of YBCO structures by traditional methods, as a rule, some compromise is reached, namely, films with acceptable morphology are used, but with reduced electrophysical parameters. In this paper, it is shown that YBCO bridges up to 4 microns wide with perfect surface morphology, i.e. free from defects, with a critical current density Jc ≥ 3106 A/cm2 at a temperature T = 77 K and a critical temperature Tс ≥ 88 K. can be obtained using the preliminary topology mask method. Moreover, the perfect morphology of the bridge surface, the values of the critical current density and the critical temperature are preserved even after repeated (additional) deposition of the YBCO layer on the structure with the preliminary topology mask. Based on the results obtained in a series of fifteen samples, it is concluded that, in contrast to the electrophysical characteristics, it is not enough to fix the standard (basic) parameters of the growth process for the stable implementation of the perfect surface morphology of YBCO films.

Impact of Eu Nanoparticles Substitution for Ca Site in Bi(Pb)-2223 Cuprates Superconductor

2020 ◽  
Vol 301 ◽  
pp. 202-208
Author(s):  
E.S. Nurbaisyatul ◽  
H. Azhan ◽  
Kasim Azman ◽  
Norazila Ibrahim ◽  
Siti Fatimah Saipuddin
Keyword(s):  
Critical Temperature ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Solid State Reaction Method ◽  
Nominal Composition ◽  
Superconducting Properties ◽  
X Ray Diffraction ◽  
Effective Surface ◽  
X Ray

The sample with nominal composition of Bi1.6Pb0.4Sr2Ca2-xEuxCu3Oy where x = 0.000, 0.0025, 0.020, 0.050 and 0.100 were synthesized through solid state reaction method. The effect of Eu2O3 nanoparticles doping on the superconducting and structural properties were studied by means of critical temperature, TC, critical current density, JC, X-ray diffraction (XRD) and field emission scanning electron microscopy (FESEM). The amount of 2223 phase gradually decreased with the increment of Eu concentration which indicates that Eu nanoparticles substitution at Ca site favours the growth of 2212 phases. The sample with higher porosity was found to be decreased in critical temperature, TC as well as critical current density, JC due to the lack of effective surface area for current flowing. The best superconducting properties were observed at x = 0.0025 substitutes into Ca site for Bi (Pb)-2223 host sample.

The Effects of Nanoparticle Addition in Bi-2212 Superconductors

2014 ◽  
Vol 69 (2) ◽  
Author(s):  
M. A. Suazlina ◽  
S. Y. S. Yusainee ◽  
H. Azhan ◽  
R. Abd-Shukor ◽  
R. M. Mustaqim
Keyword(s):  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Density Measurement ◽  
Solid State Reaction Method ◽  
Crystallographic Structure ◽  
Superconducting Properties ◽  
X Ray Diffraction ◽  
Oxide Powders ◽  
Critical Current Density Jc

The effect of Y2O3 nanoparticle addition on the superconducting properties of Bi1.6Pb0.4Sr 2CaCu 2Oy have been investigated. The samples were prepared using high purity oxide powders via solid state reaction method. Y2O3 nanoparticle with 0.0-1.0 wt. % was systematically added to the well balanced Bi1.6Pb0.4 Sr2CaCu2Oy before sinter in order to trace the existense of nanoparticle addition in the system. The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and critical current density, Jc. The current density measurement was done via four-point probe method under zero magnetic fields. The critical current density, Jc and superconductivity transition temperature, Tc for sample with addition of Y2O3 nanoparticle were found to be higher than the pure sample. The optimal addition of Y2O3 nanoparticle to the sample Bi-2212 system was found at 0.7 wt. %. The crystallographic structure of all samples was evidenced to be orthorhombic where a ≠ b ≠ c. Changes in superconducting properties of Y2O3 nanoparticle added Bi-2212 system were discussed.

Effect of Nano-Sized Sm2BaCuO5 Particles Addition on the Pinning Mechanism of Sm–Ba–Cu–O Materials

2004 ◽  
Vol 19 (3) ◽  
pp. 843-850 ◽  
Author(s):  
Shih-Yun Chen ◽  
Ping-Chi Hseih ◽  
In-Gann Chen ◽  
Mow-Kuen Wu
Keyword(s):  
Critical Temperature ◽  
Magnetic Fields ◽  
Critical Current Density ◽  
The Other ◽  
High Magnetic Fields ◽  
Superconducting Properties ◽  
Pinning Mechanism ◽  
Pinning Centers ◽  
Crystalline Defects ◽  
Control Samples

The superconducting properties of air-processed melt-textured growth Sm–Ba–Cu–O samples with addition of small amounts (0.004 wt%, 0.4 wt%, 4 wt%) of nano-sized Sm2BaCuO5 particles (nm211) were studied. The microstructure observations show that the size distribution and morphology of the 211-particles of the nm211-doped samples are similar to that of the control (undoped) samples. However, except for the 4 wt% nm211-doped sample, both Tc (critical temperature) and Jc (H, T) (critical current density) are enhanced in nm211-doped samples, and the Jc–H curves are different from those of control samples. The effect of nm211 particles on Jc enhancement is larger at high magnetic fields (>1 T at 77 K) than at low magnetic fields (0∼1 T). The dominant pinning mechanism by analyzing the Jc (H, T) data using the scaling theory indicate that the nm211-doped samples are originated from Δκ pinning (i.e., Tc variation); on the other hand, the control samples are originated from normal pinning (i.e., nonsuperconducting crystalline defects). It is proposed that nano-sized compositional fluctuations in the RE1+x Ba2−x Cu3O y matrix, which are products of nm211 particles and liquid peritectic reaction, act as the source of Δκ pinning centers.

Short Review on Rare Earth and Metalloid Oxide Additions to MgB2 as a Candidate Superconducting Material for Medical Applications

2015 ◽  
Vol 638 ◽  
pp. 357-362 ◽  
Author(s):  
Dan Batalu ◽  
Gheorghe Aldica ◽  
Mihail Burdusel ◽  
Petre Badica
Keyword(s):  
Magnetic Field ◽  
Rare Earth ◽  
Critical Temperature ◽  
Critical Current Density ◽  
Strong Influence ◽  
Short Review ◽  
Medical Applications ◽  
Superconducting Properties ◽  
Magnetic Coils ◽  
Complex Optimization

MgB2 is a candidate for the fabrication of magnetic coils used in medical applications. Our review indicate that oxide additions based on the rare earth or metalloid elements show improvement of the MgB2 critical current density (Jc) and the irreversible magnetic field (Hirr) without significantly affecting the critical temperature (Tc) However, the characteristics of the additions and the technological approaches show a strong influence in controlling superconducting properties. Both additions and the technology need a careful and complex optimization in order to enhance the Jc and Hirr.

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