References of "Fagnard, Jean-François"
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See detailDC and AC Shielding Properties of Bulk High-Tc Superconducting Tubes
Fagnard, Jean-François ULg; Denis, Samuel; Lousberg, Grégory ULg et al

in IEEE Transactions on Applied Superconductivity (2009), 19(3), 2905-2908

We have studied numerically and experimentally the magnetic flux penetration in high-Tc superconducting tube subjected to a uniform magnetic field parallel to its long axis. This study is carried in view ... [more ▼]

We have studied numerically and experimentally the magnetic flux penetration in high-Tc superconducting tube subjected to a uniform magnetic field parallel to its long axis. This study is carried in view of designing low-frequency magnetic shields by exploiting the diamagnetic properties of high-Tc superconducting ceramics. We have measured the field attenuation for applied magnetic fields in the frequency range 5 mHz-0.1 Hz by Hall probe measurements and at audio frequencies using a sensing coil. A simple 1D analysis using the Kim critical state model was found to be able to reproduce the experimental data satisfactorily. We have also determined the phase shift between the internal and the applied field both experimentally and numerically. Finally, we have studied the sweep rate dependence of the magnetic shielding properties, using data recorded either at several constant sweep rates dB/dt or at several AC fields of various amplitudes and frequencies. Both methods agree with each other and lead to a n -value of the E ~ J n law equal to ~ 40 at 77 K. [less ▲]

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See detailMeasurement of the magnetic field inside the holes of a drilled bulk high-Tc superconductor
Lousberg, Grégory ULg; Fagnard, Jean-François ULg; Noudem, Jacques G et al

in Superconductor Science and Technology (2009), 22

We use macroscopic holes drilled in a bulk YBCO superconductor to probe its magnetic properties in the volume of the sample. The sample is subjected to an AC magnetic flux with a density ranging from 30 ... [more ▼]

We use macroscopic holes drilled in a bulk YBCO superconductor to probe its magnetic properties in the volume of the sample. The sample is subjected to an AC magnetic flux with a density ranging from 30 to 130 mT and the flux in the superconductor is probed by miniature coils inserted in the holes. In a given hole, three different penetration regimes can be observed: (i) the shielded regime, where no magnetic flux threads the hole; (ii) the gradual penetration regime, where the waveform of the magnetic field has a clipped sine shape whose fundamental component scales with the applied field; and (iii) the flux concentration regime, where the waveform of the magnetic field is nearly a sine wave, with an amplitude exceeding that of the applied field by up to a factor of two. The distribution of the penetration regimes in the holes is compared with that of the magnetic flux density at the top and bottom surfaces of the sample, and is interpreted with the help of optical polarized light micrographs of these surfaces. We show that the measurement of the magnetic field inside the holes can be used as a local characterization of the bulk magnetic properties of the sample. [less ▲]

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See detailMagneto transport characterization of the Sn-doped TbMnO3 manganites
Pekala, Marek; Drozd, V.; Fagnard, Jean-François ULg et al

in Journal of Alloys & Compounds (2009), 467(1-2), 35-40

The structural, magnetic and electrical transport properties of the Sn-doped TbMnO3 manganites are studied by X-ray diffraction, ac susceptibility, dc magnetization and electrical resistivity measurements ... [more ▼]

The structural, magnetic and electrical transport properties of the Sn-doped TbMnO3 manganites are studied by X-ray diffraction, ac susceptibility, dc magnetization and electrical resistivity measurements. The Sn doping into the Tb and Mn sites of TbMnO3 compresses the unit cell and changes parameters of the antiferromagnetic phase whereas the magnetic moment of Mn are only weakly affected. The electrical resistivity of doped manganites is reduced and the activation energy EA is determined for the thermally activated conduction. [less ▲]

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See detailMagnetotransport of La0.5Ba0.5MnO3
Pekala, Marek; Drozd, V.; Fagnard, Jean-François ULg et al

in Journal of Applied Physics (2009), 105(1), 013923-013923-8

Physical properties of polycrystalline La0.5Ba0.5MnO3 are reported from low temperature (10 K) up to above room temperature. An aim has been to obtain microscopic parameters and to search for the ... [more ▼]

Physical properties of polycrystalline La0.5Ba0.5MnO3 are reported from low temperature (10 K) up to above room temperature. An aim has been to obtain microscopic parameters and to search for the characteristic lengths in terms of which one can discuss the interplay between magnetic, electric, and phonon excitations. The structural and magnetotransport measurements reveal a set of relatively high transition temperatures (near 300 K) between ferromagnetic/metallic and paramagnetic/semiconducting phases. It is found, in particular, that the so-called localization length increases from 0.085 to 0.24 nm when the magnetic field varies from 0 to 8 T. Moreover a “special field value” ~0.03 T is observed in the description of the electrical resistance. It cannot be presently distinguished whether it is the signature of a spin reorientation transition in the canted phase or a mere saturation field for aligning magnetic domains. The relatively high magnetoresistance effect (~=55% at 8 T and 10 K) makes the La0.5Ba0.5MnO3 a very interesting material for among others sensor applications. [less ▲]

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See detailMagnetocaloric effect in nano- and polycrystalline manganite La0.7Ca0.3MnO3
Pekala, Marek; Drozd, V.; Fagnard, Jean-François ULg et al

in Applied Physics A : Materials Science & Processing (2008), 90(2), 237-241

La0.7Ca0.3MnO3 samples were prepared in nano- and polycrystalline forms by the sol-gel and solid state reaction methods, respectively, and structurally characterized by synchrotron X-ray diffraction. The ... [more ▼]

La0.7Ca0.3MnO3 samples were prepared in nano- and polycrystalline forms by the sol-gel and solid state reaction methods, respectively, and structurally characterized by synchrotron X-ray diffraction. The magnetic properties determined by ac susceptibility and dc magnetization measurements are discussed. The magnetocaloric effect in this nanocrystalline manganite is spread over a broader temperature interval than in the polycrystalline case. The relative cooling power of the poly- and nanocrystalline manganites is used to evaluate a possible application for magnetic cooling below room temperature. [less ▲]

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See detailAn ac susceptometer for the characterization of large, bulk superconducting samples
Laurent, Philippe ULg; Fagnard, Jean-François ULg; Vanderheyden, Benoît ULg et al

in Measurement Science & Technology (2008), 19(8), 085705

The main purpose of this work was to design, develop and construct a simple, low-cost ac susceptometer to measure large, bulk superconducting samples (up to 32 mm in diameter) in the temperature range ... [more ▼]

The main purpose of this work was to design, develop and construct a simple, low-cost ac susceptometer to measure large, bulk superconducting samples (up to 32 mm in diameter) in the temperature range 78–120 K. The design incorporates a double heating system that enables a high heating rate (25 K h−1) while maintaining a small temperature gradient (<0.2 K) across the sample. The apparatus can be calibrated precisely using a copper coil connected in series with the primary coil. The system has been used successfully to measure the temperature dependence of the ac magnetic properties of entire RE–Ba–Cu–O [(RE)BCO] bulk superconducting domains. A typical ac susceptibility measurement run from 78 K to 95 K takes about 2 h, with excellent temperature resolution (temperature step ∼ 4 mK) around the critical temperature, in particular. [less ▲]

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See detailUnusual resistivity hysteresis in a bulk magnetoresistive ferromagnetic/ferrimagnetic composite (La0.7Ca0.3MnO3/Mn3O4): Role of demagnetization effects
Vertruyen, Bénédicte ULg; Cloots, Rudi ULg; Ausloos, Marcel ULg et al

in Applied Physics Letters (2007), 91(6), 062514

The authors report an intriguing resistivity versus magnetic field dependence in polycrystalline composite samples containing a magnetoresistive manganite (ferromagnetic/conducting La0.7Ca0.3MnO3) and a ... [more ▼]

The authors report an intriguing resistivity versus magnetic field dependence in polycrystalline composite samples containing a magnetoresistive manganite (ferromagnetic/conducting La0.7Ca0.3MnO3) and a magnetic manganese oxide (ferrimagnetic/insulating Mn3O4). At 10 K, when the magnetic field is scanned from positive to negative values, the resistance peak occurs at positive magnetic field, instead of zero or negative field as usually observed in polycrystalline manganite samples. The position of the resistance peak agrees well with the cancellation of the internal magnetic field, suggesting that the demagnetization effects are responsible for this behavior. (c) 2007 American Institute of Physics. [less ▲]

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See detailMagnetocaloric effect and magnetic properties of Tb0.9Sn0.1MnO3
Fabris, Frederik Wolff; Pekala, Marek; Drozd, V. et al

in Journal of Applied Physics (2007), 101(10), 103904

The magnetocaloric effect in magnetic materials is of great interest nowadays. In this article we present an investigation about the magnetic properties near the magnetic transition in a polycrystalline ... [more ▼]

The magnetocaloric effect in magnetic materials is of great interest nowadays. In this article we present an investigation about the magnetic properties near the magnetic transition in a polycrystalline sample of a manganite Tb0.9Sn0.1MnO3. Particularly, we are interested in describing the nature of the magnetic interactions and the magnetocaloric effect in this compound. The temperature dependence of the magnetization was measured to determine the characteristics of the magnetic transition and the magnetic entropy change was calculated from magnetization curves at different temperatures. The magnetic solid is paramagnetic at high temperatures. We observe a dominant antiferromagnetic interaction below T-n=38 K for low applied magnetic fields; the presence of Sn doping in this compound decreases the Neel temperature of the pure TbMnO3 system. A drastic increase in the magnetization as a function of temperature near the magnetic transition suggests a strong magnetocaloric effect. We found a large magnetic entropy change Delta S-M(T) of about -4 J/kg K at µ0H=3 T. We believe that the magnetic entropy change is associated with the magnetic transition and we interpret it as due to the coupling between the magnetic field and the spin ordering. This relatively large value and broad temperature interval (about 35 K) of the magnetocaloric effect make the present compound a promising candidate for magnetic refrigerators at low temperatures. (c) 2007 American Institute of Physics. [less ▲]

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See detailDoes the orbital degeneracy play any role in the high thermopower of lamellar cobaltites?
Pollet, M.; Doumerc, J. P.; Guilmeau, E. et al

in Journal of Applied Physics (2007), 101(8),

This article investigates the role of the CoO6 octahedron distortion on the electronic properties and more particularly on the high value of the Seebeck coefficient in the BiCaCoO lamellar cobaltites. Our ... [more ▼]

This article investigates the role of the CoO6 octahedron distortion on the electronic properties and more particularly on the high value of the Seebeck coefficient in the BiCaCoO lamellar cobaltites. Our measurements provide clues indicating that the t2g orbital degeneracy lifting has to be considered to account for the observed high temperature limit of the thermopower. They also provide experimental arguments for locating the a1g and eg′ orbitals levels on the energy scale, through the compression of the octahedron. These results are in agreement with recent ab initio calculation including the electronic correlations and concluding for the inversion of these levels as compared to the expectation from the crystal field theory. © 2007 American Institute of Physics. [less ▲]

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See detailElectrical transport and percolation in magnetoresistive manganite/insulating oxide composites: Case of La0.7Ca0.3MnO3/Mn3O4
Vertruyen, Bénédicte ULg; Cloots, Rudi ULg; Ausloos, Marcel ULg et al

in Physical Review. B (2007), 75(16), 165112

We report the results of electrical resistivity measurements carried out on well-sintered La0.7Ca0.3MnO3/Mn3O4 composite samples with almost constant composition of the magnetoresistive manganite phase ... [more ▼]

We report the results of electrical resistivity measurements carried out on well-sintered La0.7Ca0.3MnO3/Mn3O4 composite samples with almost constant composition of the magnetoresistive manganite phase (La0.7Ca0.3MnO3). A percolation threshold (phi c) occurs when the La0.7Ca0.3MnO3 volume fraction is ~ 0.19. The dependence of the electrical resistivity rho as a function of La0.7Ca0.3MnO3 volume fraction fLCMO can be described by percolationlike phenomenological equations. Fitting the conducting regime (fLCMO > phic) by the percolation power law rho # (fLCMO - phic)^(-t) returns a critical exponent value of 2.0±0.2 at room temperature and 2.6±0.2 at 5 K. The increase of t is ascribed to the influence of the grain boundaries on the electrical conduction process at low temperature. (C) 2007 The American Physical Society. [less ▲]

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See detailElectrical transport and magnetic properties of Mn3O4-La0.7Ca0.3MnO3 ceramic composites prepared by a one-step spray-drying technique
Vertruyen, Bénédicte ULg; Fagnard, Jean-François ULg; Vanderbemden, Philippe ULg et al

in Journal of the European Ceramic Society (2007), 27(13-15), 3923-3926

La0.7Ca0.3MnO3/Mn3O4 composites can be synthesized in one step by thermal treatment of a spray-dried precursor, instead of mixing pre-synthesized powders. Another advantage of this composite system is ... [more ▼]

La0.7Ca0.3MnO3/Mn3O4 composites can be synthesized in one step by thermal treatment of a spray-dried precursor, instead of mixing pre-synthesized powders. Another advantage of this composite system is that a long sintering step can be used without leading to significant modification of the manganite composition. The percolation threshold is reached at ~ 20 vol% of manganite phase. The 77 K low field magnetoresistance is enhanced to ~ 11 % at 0.15 T when the composition is close to the percolation threshold. (c) 2007 Elsevier Ltd. All rights reserved. [less ▲]

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See detailLiMn2-xTixO4 spinel-type compounds (x <= 1): Structural, electrical and magnetic properties
Krins, Natasha ULg; Hatert, Frédéric ULg; Traina, Karl ULg et al

in Solid State Ionics (2006), 177(11-12), 1033-1040

LiMn2-xTixO4 compounds with 0.5 =<x =< 1 were prepared by solid state reaction and Pechini technique. Powder X-ray diffraction showed that all samples crystallize with the spinel crystal structure (S.G ... [more ▼]

LiMn2-xTixO4 compounds with 0.5 =<x =< 1 were prepared by solid state reaction and Pechini technique. Powder X-ray diffraction showed that all samples crystallize with the spinel crystal structure (S.G. Fd3m). The cubic unit-cell parameter increases with the Ti content. The influence of the Ti content and cationic distribution on the magnetic properties of the compounds was studied by measuring the temperature and magnetic field dependences of the magnetization: substitution by non-magnetic d(0) Ti4+ ions appeared to weaken the magnetic interactions between the manganese ions. The electrical properties of LiMnTiO4 were studied by AC impedance spectroscopy and DC polarisation measurements, which revealed the electronic character of the conduction process. (c) 2006 Elsevier B.V. All rights reserved. [less ▲]

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See detailYBa2Cu3O(7-delta) thick films on Ag prepared by the electrophoretic deposition technique
Dusoulier, Laurent; Denis, Samuel; Fagnard, Jean-François ULg et al

in Journal of Physics: Conference Series (2006), 43

YBa2Cu3O7-δ thick films have been deposited onto Ag substrates by the Electrophoretic Deposition (EPD) technique. Different microstructures and electrical behaviours were observed depending on the ... [more ▼]

YBa2Cu3O7-δ thick films have been deposited onto Ag substrates by the Electrophoretic Deposition (EPD) technique. Different microstructures and electrical behaviours were observed depending on the starting powder. Coatings prepared from commercial powder displayed significant porosity and the superconducting transition width was found to be magnetic-field dependent. Films produced from home-made coprecipitated powder are denser but contain some secondary phases. No dependence of the resistive transition as a function of magnetic field (H ≤ 20 Oe) was observed in that case. [less ▲]

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See detailStudy of thermal effects in bulk RE-BCO superconductors submitted to a variable magnetic field
Laurent, Philippe; Fagnard, Jean-François ULg; Mathieu, J.-P. et al

in Journal of Physics: Conference Series (2006), 43

When bulk RE-BCO superconductors are used as permanent magnets in engineering applications, they are likely to experience transient variations of the applied magnetic field. The resulting vortex motion ... [more ▼]

When bulk RE-BCO superconductors are used as permanent magnets in engineering applications, they are likely to experience transient variations of the applied magnetic field. The resulting vortex motion may cause a significant temperature increase. As a consequence the initial trapped flux is reduced. In the present work, we first focus on the cause of a temperature increase. The temperature distribution within a superconducting finite cylinder subjected to an alternating magnetic field is theoretically predicted. Results are compared to experimental data obtained by two temperature sensors attached to a bulk YBCO pellet. Second, we consider curative methods for reducing the effect of heat flux on the temperature increase. Hall-probe mappings on YBCO samples maintained out of the thermal equilibrium are performed for two different morphologies : a plain single domain and a single domain with a regularly spaced hole array. The drilled single-domain displays a trapped induction which is weakly affected by the local heating while displaying a high trapped field. [less ▲]

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See detailUse of a High-Temperature Superconducting Coil for Magnetic Energy Storage
Fagnard, Jean-François ULg; Crate, David; Jamoye, Jean-François et al

in Institute of Physics Conference Series (2006), 43

A high temperature superconducting magnetic energy storage device (SMES) has been realised using a 350 m-long BSCCO tape wound as a ''pancake'' coil. The coil is mounted on a cryocooler allowing ... [more ▼]

A high temperature superconducting magnetic energy storage device (SMES) has been realised using a 350 m-long BSCCO tape wound as a ''pancake'' coil. The coil is mounted on a cryocooler allowing temperatures down to 17.2 K to be achieved. The temperature dependence of coil electrical resistance R(T) shows a superconducting transition at T = 102.5 K. Measurements of the V(I) characteristics were performed at several temperatures between 17.2 K and 101.5 K to obtain the temperature dependence of the critical current (using a 1 uV/cm criterion). Critical currents were found to exceed 100 A for T < 30 K. An electronic DC-DC converter was built in order to control the energy flow in and out of the superconducting coil. The converter consists of a MOS transistor bridge switching at a 80 kHz frequency and controlled with standard Pulse Width Modulation (PWM) techniques. The system was tested using a 30 V squared wave power supply as bridge input voltage. The coil current, the bridge input and output voltages were recorded simultaneously. Using a 10 A setpoint current in the superconducting coil, the whole system (coil + DC-DC converter) can provide a stable output voltage showing uninterruptible power supply (UPS) capabilities over 1 s. [less ▲]

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See detailSpin-cluster effect and lattice-deformation-induced Kondo effect, spinglass freezing, and strong phonon scattering in La0.7Ca0.3Mn1-xCrxO3
Wu, Bai-Mei; Li, Bo; Zhen, Wei-Hua et al

in Journal of Applied Physics (2005), 97(10, Part 1), 103908

Besides the Kondo effect observed in dilute magnetic alloys, the Cr-doped perovskite manganate compounds La0.7Ca0.3Mn1-xCrxO3 also exhibit Kondo effect and spin-glass freezing in a certain composition ... [more ▼]

Besides the Kondo effect observed in dilute magnetic alloys, the Cr-doped perovskite manganate compounds La0.7Ca0.3Mn1-xCrxO3 also exhibit Kondo effect and spin-glass freezing in a certain composition range. An extensive investigation for the La0.7Ca0.3Mn1-xCrO3 (x=0.01, 0.05, 0.10, 0.3, 0.6, and 1.0) system on the magnetization and ac susceptibility, the resistivity and magnetoresistance, as well as the thermal conductivity is done at low temperature. The spin-glass behavior has been confirmed for these compounds with x=0.05, 0.1, and 0.3. For temperatures above T-f (the spin-glass freezing temperature) a Curie-Weiss law is obeyed. The paramagnetic Curie temperature 0 is dependent on Cr doping. Below T-f there exists a Kondo minimum in the resistivity. Colossal magnetoresistance has been observed in this system with Cr concentration up to x=0.6. We suppose that the substitution of Mn with Cr dilutes Mn ions and changes the long-range ferromagnetic order of La0.7Ca0.3MnO3. These behaviors demonstrate that short-range ferromagnetic correlation and fluctuation exist among Mn spins far above T-f. Furthermore, these interactions are a precursor of the cooperative freezing at T-f. The "double bumps" feature in the resistivity-temperature curve is observed in compounds with x= 0.05 and 0.1. The phonon scattering is enhanced at low temperatures, where the second peak of double bumps comes out. The results indicate that the spin-cluster effect and lattice deformation induce Kondo effect, spin-glass freezing, and strong phonon scattering in mixed perovskite La0.7Ca0.3Mn1-xCrO3. (c) 2005 American Institute of Physics. [less ▲]

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See detailLow-field magnetoresistance in La0.7Ca0.3MnO3 manganite compounds prepared by the spray drying technique
Vertruyen, Bénédicte ULg; Rulmont, André ULg; Cloots, Rudi ULg et al

in Journal of Materials Science (2005), 40(1), 117-122

Calcium-substituted lanthanum manganite compounds were synthesized by the spray drying technique. This method - whose main advantages are versatility, high reproducibility and scalability - yields small ... [more ▼]

Calcium-substituted lanthanum manganite compounds were synthesized by the spray drying technique. This method - whose main advantages are versatility, high reproducibility and scalability - yields small grain materials of high homogeneity and displaying low-field magnetoresistance effects. We report about the physical and chemical characterizations of these samples in order to investigate the potential interest of spray drying for the production of materials for low-field magnetoresistance applications. We have studied the dependence of the low-field magnetoresistance on the temperature and duration of the thermal treatment applied to the pelletized powders. The issue of the shape anisotropy (demagnetisation effects) influence on the magnetoresistance properties has also been dealt with. (C) 2005 Springer Science + Business Media, Inc. [less ▲]

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See detailSilver paint as a soldering agent for DyBaCuO single-domain welding
Mathieu, Jean-Philippe; Fagnard, Jean-François ULg; Laurent, Philippe ULg et al

in Superconductor Science and Technology (2005), 18(4), 508-512

Silver paint has been tested as a soldering agent for DyBaCuO 4 single-domain welding. Junctions have been manufactured on Dy-Ba-Cu-O single domains cut either along planes parallel to the c-axis IT or ... [more ▼]

Silver paint has been tested as a soldering agent for DyBaCuO 4 single-domain welding. Junctions have been manufactured on Dy-Ba-Cu-O single domains cut either along planes parallel to the c-axis IT or along the ab-planes. Microstructural and superconducting characterizations of the samples have been performed. For both types of junctions, the microstructure in the joined area is very clean: no secondary phase or Ag particle segregation has been observed. Electrical and magnetic measurements for all configurations of interest are reported (rho(T) curves, and Hall probe mapping). The narrow resistive superconducting transition reported for all configurations shows that the artificial junction does not affect significantly the measured superconducting properties of the material. [less ▲]

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See detailSpin glass behaviour and spin-dependent scattering in La0.7Ca0.3Mn0.9Cr0.1O3 perovskites
Wu, B. M.; Ausloos, Marcel ULg; Du, Y. L. et al

in Chinese Physics Letters (2005), 22(3), 686-689

The magnetic, electrical and thermal transport properties of the perovskite La0.7Ca0.3Mn0.9Cr0.1O3 have been investigated by measuring dc magnetization, ac susceptibility, the magnetoresistance and ... [more ▼]

The magnetic, electrical and thermal transport properties of the perovskite La0.7Ca0.3Mn0.9Cr0.1O3 have been investigated by measuring dc magnetization, ac susceptibility, the magnetoresistance and thermal conductivity in the temperature range of 5-300 K. The spin glass behaviour with a spin freezing temperature of 70 K has been well confirmed for this compound, which demonstrates the coexistence and competition between ferromagnetic and antiferromagnetic clusters by the introduction of Cr. Colossal magnetoresistance has been observed over the temperature range investigated. The introduction of Cr causes the "double-bump" feature in electrical resistivity rho(T). Anomalies on the susceptibility and the thermal conductivity associated with the double-bumps in rho(T) are observed simultaneously. The imaginary part of ac susceptibility shows a sharp peak at the temperature of insulating-metallic transition where the first resistivity bump was observed, but it is a deep-set valley near the temperature where the second bump in rho(T) emerges. The thermal conductivity shows an increase below the temperature of the insulating metallic transition, but the phonon scattering is enhanced accompanying the appearance of the second peak of double-bumps in rho(T). We relate those observed in magnetic and transport properties of La0.7Ca0.3Mn0.9Cr0.1O3 to the spin-dependent scattering. The results reveal that the spin-phonon interaction may be of more significance than the electron (charge)-phonon interaction in the mixed perovskite system. [less ▲]

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See detailInvestigation of DyBa2CU3O7-d superconducting domains grown by the infiltration technique starting with small size Dy-211 particles
Mathieu, Jean-Philippe; Koutzarova, T.; Rulmont, André ULg et al

in Superconductor Science and Technology (2005), 18(2 Sp. Iss. SI), 136-141

An infiltration and growth process is here used as an alternative to the classical top-seeded melt-textured growth process for the production of Dy-123 single-domains with finely dispersed small size Dy ... [more ▼]

An infiltration and growth process is here used as an alternative to the classical top-seeded melt-textured growth process for the production of Dy-123 single-domains with finely dispersed small size Dy-211 particles. The starting materials are the 211-particles and a barium and copper rich liquid phase precursor. The infiltration and growth process allows for controlling both the spatial and size distribution of the 211-particles in the final superconducting 123-single-domain. The main parameters (set-ups, maximum processing temperature with respect to the peritectic temperature, nature of reactant, porosity of the 211-preform) of the infiltration and growth process are discussed. Moreover, different processes of chimie douce are shown in order to produce Dy-211 particles with controlled shape and size, particles that can be used as precursors for the infiltration and growth process. [less ▲]

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