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Applied Superconductivity, IEEE Transactions on

Issue 2 • Date June 2007

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Displaying Results 1 - 25 of 319
  • Table of contents

    Publication Year: 2007 , Page(s): C1
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  • IEEE Transactions on Applied Superconductivity publication information

    Publication Year: 2007 , Page(s): C2
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  • Table of contents

    Publication Year: 2007 , Page(s): 2517 - 2529
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    Publication Year: 2007 , Page(s): 2530
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  • Maxwell's Equations in Superconductors

    Publication Year: 2007 , Page(s): 2531 - 2536
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (130 KB) |  | HTML iconHTML  

    A discussion is given of the various ways of defining fields in normal metals and superconductors. Josephson and Evetts used different approaches but they lead to the same results. The Evetts formulation, based on the chemical potential of a vortex line, leads to the development of thermo-electric equations using irreversible thermodynamics. The magnetic field terms in the Ginzburg-Landau free energy are discussed. An alternative is to use macroscopic quantities rather local ones. These are the external field and total moment of a body. View full abstract»

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  • YBa2Cu3O7 Coated Conductor Grown by Hybrid Liquid Phase Epitaxy

    Publication Year: 2007 , Page(s): 2537 - 2541
    Cited by:  Papers (1)  |  Patents (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (805 KB) |  | HTML iconHTML  

    The hybrid liquid phase epitaxy (HLPE) approach has the potential to be a high rate-low cost process. This deposition process is used to grow epitaxial YBa2Cu3O7 (YBCO) films in the presence of a thin (100 to 500 nm) liquid BaO-CuO flux layer. Despite the presence of the molten flux, YBCO growth is found to be feasible on technical substrates because of the limited dissolution of the buffer layer in the thin flux layer. The high atom mobility at the growing interface under the liquid flux enables high growth rates (demonstrated to be greater than 10 nmldrs-1 in a wide temperature regime and predicted to be up to ~5 nmldrs-1). We report results on HLPE YBCO films grown on (100) strontium titanate and textured technical substrates such as rolling-assisted biaxially textured substrates (RABiTS) and ion-beam-assisted-deposited (IBAD) MgO. High values of the critical temperature above 90 K and critical current ~400 A per cm width for 3 mum thick films on single crystal substrates and promising high values on technical substrates are obtained. Furthermore, there is potential for making thicker films of the same quality since film density is maintained with thickness. Angular-dependent transport critical current as a function of applied field for these films, as well as microstructural measurements by transmission electron microscopy are also reported. The angular and field dependence of critical current density are similar to standard PLD (pulsed laser deposition) films. Although the films are of high epitaxial quality they contain yttria precipitates which are possible sources of flux pinning centers. View full abstract»

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  • Superconducting Properties of V-Ti Alloys

    Publication Year: 2007 , Page(s): 2542 - 2545
    Cited by:  Papers (1)
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    The effects of alpha-Ti depositions, caused with the heat treatments at 300-500degC, were studied for various V-Ti alloys through measurements of Tc, Ic, and X-ray diffraction patterns. Jc increased with the alpha-Ti depositions for the V-Ti alloys with various Ti contents. The alpha-Ti depositions are very effective pinning centers in V-Ti alloys, being similar to those in Nb-Ti alloys. The maximum Tc of 8.2 K was obtained for the V-40at%Ti alloy annealed at 500degC for 2 hr, while the maximum Birr(4.2 K) of 8.5 T was obtained for the V-(50-60) at%Ti alloys. Jc (4.2 K, and 6.5 T) of about 170 A/mm2 was obtained for the V-45at%Ti alloy annealed at 500deg C for 4 hr. We also fabricated the V-Ti alloy multifilament;!!} wires in order to stabilize the alloy superconductors. The final cold-drawing after heat treatment at 400-450degC is effective on the improvements of Tc, Birr, and Jc of the multifilamentary V-(40-45)at%Ti alloy wires. Jc(4.2 K, 6.5 T) of 200 A /mm2 was obtained for the multifilamentary wire. View full abstract»

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  • AC Losses and Critical Current Densities of NbTi/Cu Multifilamentary Tapes

    Publication Year: 2007 , Page(s): 2546 - 2549
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (691 KB) |  | HTML iconHTML  

    Several kinds of NbTi/Cu multifilamentary tapes with high aspect-ratio cross-sections were fabricated in order to develop new conductors used for windings of conduction-cooled LTS pulse- coils with both low ac losses and high stability. These tapes were obtained by the cold rolling process from normal multifilamentary wires. For the edge-on transverse magnetic field at 4.2 K, about 20% increases in critical current densities at 6 T were observed for the tape with the highest aspect ratio of 7.4, and its hysteresis losses estimated from the observed magnetization were reduced to approximately one-half of those in the original wire. In this edge-on filed condition, the observed coupling losses in the tape were also decreased to about 1/17 times as large as those in the original wire. These experimental results showed that the NbTi/Cu multifilamentary tape had strong anisotropy of electromagnetic properties such as critical currents, hysteresis losses, and coupling losses and that good performances were obtained for edge-on transverse magnetic fields. View full abstract»

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  • The History of Technical Superconductors Development in Russia

    Publication Year: 2007 , Page(s): 2550 - 2555
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2975 KB) |  | HTML iconHTML  

    The history of technical superconductivity in the USSR and later in the Russian Federation (RF) is very tightly connected with the name of Anatoly Nikulin one of the leading scientist of the Bochvar Institute. He made major contribution to the field of superconductivity in the RF as an applied scientist and as a leader of the National Program on the development of industrial production of the technical superconducting materials in previous Soviet Union and than in Russia. A brief review of main advances in superconducting strands technology is presented. The evolution of the properties of both HTS and LTS superconductors designed and developed in Bochvar Institute is reviewed. The results of main R&D and ITER connected activities are outlined. View full abstract»

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  • Jc(T,B) and E(T) Dependencies for NbTi Strands Used in ITER PF Insert Coil

    Publication Year: 2007 , Page(s): 2556 - 2559
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (262 KB) |  | HTML iconHTML  

    In the framework of the characterization of NbTi strands manufactured by Bochvar Institute for the ITER insert coil the representative database of Jc(B,T) and E(T) was obtained. Measurements of Jc(B,T) were carried out on the samples taken from several batches of the strand at magnetic fields ranging from 5 to 9 T and temperature range from 4.2 to 7 K. All the strands were produced using the identical heat treatment route. The E(T) characteristics were recorded to simulate the current sharing temperature (Tcs) test for ITER PF coil. The Tcs compiles 6.1 K-6.3 K at magnetic field of 6 T. View full abstract»

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  • Development of Internal Tin Nb3Sn Conductor for Fusion and Particle Accelerator Applications

    Publication Year: 2007 , Page(s): 2560 - 2563
    Cited by:  Papers (23)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (887 KB) |  | HTML iconHTML  

    Performance improvements are needed for large-scale applications of Nb3Sn, such as ITER or LHC upgrades. The highest critical current density (Jc) values are achieved in distributed-barrier strand made by the Restacked Rod Process, which can reach 12 T, 4.2 K Jc values of 3000 A/mm2, with high residual resistivity ratio (RRR) values. For purposes of accelerator magnet stability, it is desirable to combine high Jc with a small effective filament diameter ( Deff ) . Initial experiments show reducing Deff from 80 mum to 40 mum leads to a 10% reduction in Jc. For fusion applications, a single-barrier design with well-spaced filaments is used to achieve the low hysteresis losses that are required. The status of our fusion strand development program is presented, including results for strand made using Nb-47 wt%Ti rods to supply Ti dopant. Such strands can reach 12 T, 4.2 K Jc> 1000 A/mm2, with losses < 1000 mJ/cm3. View full abstract»

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  • Investigation on the Effect of Ta Additions on Jc and n of (Nb,Ti)3Sn Bronze Processed Multifilamentary Wires at High Magnetic Fields

    Publication Year: 2007 , Page(s): 2564 - 2567
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    We have analyzed the influence of Ta on the superconducting properties of Ti doped bronze processed (Nb, Ta, Ti)3Sn multifilamentary wires. The study was carried out on wires with identical configuration, consisting of 14,641 filaments with 4.5 mum diameter embedded in a Ti bearing Osprey bronze and externally stabilized by copper. Several wires were made using either Nb7.5Ta or pure Nb as a filament material, some of them containing a core of NbTi as a supplementary Ti source. All wires were manufactured by three hot extrusion steps, cold drawing and several intermediate anneals. Wire samples with round and rectangular cross sections have been prepared and reacted with various heat treatments between 550 and 730degC. The residual Sn content in the Cu-Sn-Ti bronze after reaction and the degree of reaction of the filaments were determined by means of EDS and SEM analysis, respectively. AC susceptibility has been used to determine the effect of prestrain and doping on the superconducting transition temperature Tc.2 At 21 T and 4.2 K, similar non-Cu Jc values up to 90 A/mm2 (overall Jc: 63 A/mm2 ) and n values up to 25 have been observed on both compositions (Nb, Ta, Ti)3Sn and (Nb, Ti)3Sn. These results suggest that Ta as a quaternary dopant does not lead to further improvements of Jc and n of ternary (Nb, Ti)3Sn. View full abstract»

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  • Development of High Performance Nb3Sn Conductor for Fusion and Accelerator Applications

    Publication Year: 2007 , Page(s): 2568 - 2571
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1363 KB) |  | HTML iconHTML  

    While the highest field performance is a primary goal of the conductor in the next generation of particle accelerators, emphasis has been focused mainly on the increase in current carrying capacity. The conductor needed for fusion application, however, requires much lower magnetization limit along with a critical current as high as possible. The upgraded strand specifications for the International Thermonuclear Experimental Reactor (ITER) and particle accelerator applications require further improvement of current density at little expense of ac loss or effective filament diameter. A conductor designed to meet such requirements has been fabricated. The effect of heat treatment condition on its properties was investigated to develop an optimized reaction condition. Significant efforts have been made to explore the sub-element design and configuration of the strand to ensure minimum hysteresis of the wire. An attempt was also made to scale up the restack assembly unit for mass production. View full abstract»

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  • Spray-Formed High-Tin Bronze—A Homogeneous Pre-Material for Nb3Sn -Based Superconductor Wire

    Publication Year: 2007 , Page(s): 2572 - 2575
    Cited by:  Papers (1)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (741 KB) |  | HTML iconHTML  

    The advantages of high-tin bronze which is produced by the innovative process "spray forming" and its commercial application in Nb3Sn superconductor wire are presented. An important decision in the processing of Nb3Sn superconductor wire after the bronze method is the choice of pre-material. As the bronze, together with the niobium, is subjected to hot and cold forming processes, homogeneous bronze pre-material is required. High-tin bronze produced by spray forming exhibits a high degree of homogeneity. Advantages of spray-formed bronze are the very fine, equi-axed grains, the homogeneous grain structure, the reduced delta phase particle size, the minimized delta phase volume fraction and the homogeneous element distribution. These advantages are given in all spray-formed bronze qualities with tin contents up to 20%. Spray-formed bronzes with tin contents of 14.5%, 15.5% and 16.0% and an additionally titanium content up to 0.3% are commercially produced and supplied to different superconductor wire manufacturers. The processing results show that the production process stability is excellent and the results of superconducting properties are reproducible. Bronzes with tin contents of 17% and 20% have also been successfully spray-formed and formed into tubes and rods. These bronzes are now subject of investigations regarding the use in future Nb3Sn superconducting magnets with increased magnetic field strength. View full abstract»

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  • Virtual Impact Fractionation of Superconductor Precursor Powders in Inert Gas Atmosphere

    Publication Year: 2007 , Page(s): 2576 - 2579
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    Virtual impactor fractionation has been used to remove all particles over a selectable micron-sized threshold in samples of precursor powders for MgB2 and Nb3Sn superconductors. In a virtual impactor the powder is dispersed in an aerosol stream and passed through a vane geometry in which particles less than a critical size follow the gas streamlines which turn abruptly into a collection chamber, while particles larger than the critical size pass undeflected into a reject chamber. The aerosol dispersion was made in an inert gas flow in order to prevent degradation of the powder by exposure to oxygen or moisture. View full abstract»

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  • New Fabrication Process for Nb3Sn Conductors Through Diffusion Reaction Between Nb and Ag-Sn Alloys

    Publication Year: 2007 , Page(s): 2580 - 2583
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (743 KB) |  | HTML iconHTML  

    We investigated the superconducting properties of Nb3Sn formed through the diffusion reaction between Nb and Ag-Sn alloys, including Ag-9at%Sn ductile fee phase and Ag-(12-16)at%Sn ductile zeta phase alloys, and Ag-24at%Sn brittle epsiv phase alloy. We fabricated single-core and multi-core composite wires by the rod-in tube and powder-in-tube processes. The composite wires were heat treated at 650-900degC to form Nb3Sn filaments. With increase of Sn content in the Ag-Sn alloy cores, the superconducting properties of the Nb3Sn composite wires were improved. Tc and Bc2 (4.2 K) values for the Nb/Ag-Sn wires are similar to those for the Nb/Cu-Sn. However the Ic values are relatively small, due to their very thin Nb3Sn layers below 0.4 mum. Ag is apparently not effective to increase the formation rate of Nb3Sn layer. By using the 200- and 40000-core wires, Tc and Bc2 (4.2 K) values were increased by 0.5-1 K and 2-5 T, respectively for these multifllamentary wires, while from 10 to 500 times larger Ic (4.2 K) were obtained for the wires. The typical values for Tc and Bc2 (4.2 K) are 16.5-17.7 K and 16-21 T, respectively. The addition of 5at%Cu to Ag-Sn alloys improves their superconducting properties. View full abstract»

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  • Dispersion Strengthened Nb 3Sn Wire

    Publication Year: 2007 , Page(s): 2584 - 2587
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (876 KB) |  | HTML iconHTML  

    Dispersion strengthened Nb3Sn and regular Nb3Sn composites were fabricated. Their mechanical and superconducting properties were measured and compared. An increase in strength up to 10% and Jc (18 T, 4.2 K) up to 28% was achieved. The nanoparticle strengthened Cu, as a replacement of Cu, could be co-deformed with Nb to make Nb3Sn wire without changing the volume fractions of Nb and Sn and heat treatment conditions. The paper argues that nanoparticle pining effects play a major role in improvement of the properties. View full abstract»

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  • Development of Strain-Applying Apparatus for Evaluation of ITER Nb3Sn Strand

    Publication Year: 2007 , Page(s): 2588 - 2590
    Cited by:  Papers (6)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (323 KB) |  | HTML iconHTML  

    Japan Atomic Energy Agency has successfully developed Nb3Sn strand which fulfills ITER requirements. Because Nb3Sn is very susceptible to external strain which reduces critical current, critical temperature, and critical field, it is necessary to evaluate strain dependency of these Nb3Sn strands to confirm an ITER conductor design. An apparatus to measure the strain dependency was newly developed. It has a horseshoe-shaped ring and a strand is soldered on its outer surface. This shape produces uniform axial compressive or tensile strain along strand length by expanding or closing the opening of the ring. Critical current can be measured by the apparatus under a magnetic field up to 15 T, a temperature range of 4.2 K to 15 K, and strains. The maximum allowable current is about 300 A. The details of the apparatus and results of strand characterization are presented. View full abstract»

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  • Pure Bending Strain Experiments on Jacketed Nb3Sn Strands for ITER

    Publication Year: 2007 , Page(s): 2591 - 2594
    Cited by:  Papers (9)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (198 KB) |  | HTML iconHTML  

    The effect of transverse loads on strands has been pointed as a possible cause of the difference observed when scaling transport properties of single strands to those of cable-in-conduit conductors. Single multifilamentary strands inside cables are in fact subject to bending strain due to the electromagnetic forces at operating conditions and to the geometrical layout. Here the influence of pure bending strain, applied in combination with a longitudinal strain, on the critical current of advanced strands for ITER has been studied. The tested samples are single strands inserted inside a thin stainless steel jacket and wound on stainless steel barrels. After the heat treatment, a pure bending strain has been applied transferring the wires on different diameter mandrels, using ad-hoc developed and qualified techniques. Transport critical current has been measured on the single strands before and after the steel jacketing, as well as after the additional application of two different values of maximum bending strain: 0.5% and 0.25%. This was the best choice in order to verify experimentally whether the so-called long twist pitch condition can be applied for the selected strands. The distribution of the bending strain over the strand cross-section has been calculated with finite element numerical codes, and the expected critical current degradation in the limiting cases of short and long twist pitch has been computed and compared with experimental data. View full abstract»

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  • Application of Prebending Effect to Triplet Cables Using Bronze-Route Nb3Sn Strands

    Publication Year: 2007 , Page(s): 2595 - 2598
    Cited by:  Papers (3)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (741 KB) |  | HTML iconHTML  

    An application of the prebending effect to a cabling process using Nb3Sn strands was demonstrated. The prebending effect is the enhancement effect of superconducting properties due to the repeated prebending treatment for practical bronze-route Nb3Sn wires. CuNb/Nb3Sn and Cu/Nb3Sn strands were applied prebending treatment using 10 fixed pulleys with 0.8% prebending strain. Four kinds of triplets, i.e., prebent CuNb/Nb3Sn, no-prebent CuNb/Nb3Sn, prebent Cu/Nb3Sn and no-prebent Cu/Nb3Sn triplets were fabricated. Critical currents were measured for the four kinds of triplets in magnetic fields up to 11 T at 4.2 K. The obvious critical current enhancement due to the prebending effect was maintained for the prebent CuNb/Nb3Sn triplet. The results imply that the prebending treatment for high-strength Nb3Sn strands is applicable to the cable conductor fabrication. View full abstract»

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  • Scaling of the E(J) Characteristics in the ITER Type Nb3Sn Strands in Relation to the Applied Strain and Magnetic Field

    Publication Year: 2007 , Page(s): 2599 - 2602
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (164 KB) |  | HTML iconHTML  

    Voltage- current characteristics VCC(epsiv, B, 4.2 K) have been measured in the range of the applied axial tensile strain (epsiv) from 0% to 0.93% at magnetic fields 10 T and 12 T for ITER type bronze processed Nb3Sn strand and for similar strand with enhanced mechanical strength in which part of stabilizing copper was replaced by high strength high conductivity microcomposite Cu-Nb material. The results of description of the electric field-current density characteristics E(J,epsiv,B,4.2 K) are presented. To describe experimental database E( J) versus strain and magnetic field the relation is used containing four fitting parameters. Three parameters,namely: C, Tc(0) and Bc2(0, epsiv) describe. Additional parameter characterizes the smoothness of E( J). Good agreement of experiment and calculation has been obtained. View full abstract»

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  • Current Ripple Effect on n-Value

    Publication Year: 2007 , Page(s): 2603 - 2606
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (416 KB) |  | HTML iconHTML  

    We systematically studied the effect of current ripple on the determination of n-value, which is the index of the shape of the electric field-current (E-I) curve. Commercial Nb3 S n wires were measured with controlled amounts of ac ripple. Substitution- box, superconductor simulator circuits were also measured. A battery-powered current supply was used to provide the dc with ripple currents. The ripple frequencies were 60,120, and 360 Hz, to represent common electrical power harmonics in high-current power supplies. A previous study focused on the effect of ripple on the determination of dc critical current (Ic); the current study focuses on how ripple changes the n-value and shows that ripple has a larger effect on n-value than on Ic. We examined models and measurements on simulators to reproduce and explain the effects observed in measurements on superconductors. Current ripple and spikes may be sources of differences in n-values measured at different laboratories. View full abstract»

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  • RRP Nb3 Sn Strand Studies for LARP

    Publication Year: 2007 , Page(s): 2607 - 2610
    Cited by:  Papers (12)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (527 KB) |  | HTML iconHTML  

    The NbSn strand chosen for the next step in the magnet R&D of the U.S. LHC Accelerator Research Program is the 54/61 sub-element Restacked Rod Process by Oxford Instruments, Superconducting Technology. To ensure that the 0.7 mm RRP strands to be used in the upcoming LARP magnets are suitable, extensive studies were performed. Measurements included the critical current, Ic, using the voltage-current (V-I)method, the stability current, IS, as the minimal quench current obtained with the voltage-field (V-H) method, and RRR. Magnetization was measured at low and high fields to determine the effective filament size and to detect flux jumps. Effects of heat treatment temperature and durations on Ic and IS were also studied. Using strand billet qualification and tests of strands extracted from cables, the short sample limits of magnet performance were obtained. The details and the results of this investigation are herein described. View full abstract»

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  • Specific Heat, A Method to Determine the Tc Distribution in Industrial Nb3Sn Wires Prepared by Various Techniques

    Publication Year: 2007 , Page(s): 2611 - 2614
    Cited by:  Papers (8)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (693 KB) |  | HTML iconHTML  

    A new calorimeter has been built with the special purpose to determine the distribution of Tc in industrial superconducting wires. Specific heat measurements have been carried out on a series of multifilamentary Nb3Sn wires, using a long relaxation technique. The advantage of this technique consists in the fact that the measurement is performed in presence of the Cu-Sn matrix, i.e. the filaments are measured under the same stress conditions as under operation, i.e. under the same state of mechanical precompression. In addition, the Tc distribution is obtained for the whole sample volume, ruling out shielding effects. The deconvolution of the data in the region of the superconducting transition was used for getting the precise distribution of Tc, which in turn allows a determination of the Sn distribution across the filaments. These data confirm previous TEM measurements showing a Sn gradient inside of the filaments of bronze route processed Nb3Sn wires. The Tc distribution has been determined in Nb3Sn wires processed by bronze route, internal Sn and powder-in-tube technique. Based on this information, the various processing parameters can be varied to get narrower Tc distributions at transition temperatures closer to 18 K. View full abstract»

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  • Grain Growth, Morphology, and Composition Profiles in Industrial Nb3Sn Wires

    Publication Year: 2007 , Page(s): 2615 - 2618
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1644 KB) |  | HTML iconHTML  

    The A15 formation process in Nb3Sn wires has been revisited. The progress of the reaction was studied by a careful FE-SEM study after a series of heat treatments at various temperatures and times. It was found that in the very early stage of the reaction, the Sn flow is high and a very thin layer of equiaxed A15 grains is formed at the interface between Nb and the Cu-Sn bronze. Beyond the very first layer with equiaxed grains, the grains form with a columnar shape. With further progress of the A15 layer and the continuous flow of Sn through the already formed layers, a decomposition of the columnar grains to equiaxed grains was observed. By TEM/EDX, we have confirmed our earlier observation of a radial Sn gradient in the filaments. The equiaxed regions have a sufficiently high critical field to carry supercurrents at high magnetic fields, in contrast to the columnar regions, where the B values are lower, thus their contribution to the current transport at the higher fields is limited. We have also studied internal Sn wires and found equiaxed grains only, with a Sn content through the A15 layer reaching from 22 at.% to values close to 25 at.%. View full abstract»

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IEEE Transactions on Applied Superconductivity contains articles on the applications of superconductivity and other relevant technology.

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Editor-in-Chief
Britton L. T. Plourde
Syracuse University
bplourde@syr.edu
http://www.phy.syr.edu/~bplourde