The effects of granularity on the angle and field dependence of the transport Jc in coated conductors (CCs) are discussed. The granularity is revealed by scanning Hall probe microscopy of the trapped field profiles in tapes with different architectures. It was found that pulsed laser deposited (PLD) YBCO film on a RABiTS NiW substrate has the most prominent granular morphology in its trapped field profiles. This is complemented by a peculiar behavior of the critical currents when the orientation of the applied field is within a certain angular range around the ab-planes: Jc(θ) becomes independent of the angle and Jc(B) exhibits a peak. These phenomena are explained by the physics of Abrikosov–Josephson vortices at grain boundaries (GB) that leads to a transition from a GB-limited to a grain-limited regime both in Jc(θ) and Jc(B). The effects of granularity are strongly suppressed by the chemical solution deposition route for growing YBCO films on NiW, and are almost absent in PLD-YBCO on ABAD-textured templates. These results identify the collective influence of the GB on the percolative current flow in CCs, which becomes most significant at low temperatures.

Considerable progress has been made with the development of REBCO coated conductors in recent years, and high performance conductors are available commercially. For many applications, however, the cost remains prohibitive, and AC losses discourage their selection for higher frequency applications. Chemical solution deposition (CSD) methods are attractive for low-cost, scalable preparation of buffer and superconductor layers, and in many respects inkjet printing is the method of choice, permitting non-contact deposition with minimal materials wastage and excellent control of coating thickness. Highly textured coatings of YBCO and Gd-doped CeO2 have previously been reported on buffered metal substrates. Inkjet printing also introduces the possibility of patterning - directly depositing two and three dimensional structures without subtractive processing - offering a low-cost route to coated conductors with reduced AC losses. In this contribution, the inkjet deposition of superconducting YBCO tracks is reported on industrially relevant buffered metal substrates both by direct printing and an inverse patterning approach. In the latter approach, ceria tracks were printed reported, which are a candidate both for resistive filament spacers and buffer layers. TFA-based precursor solutions have been printed on SS/ABAD-YSZ/CeO2 and NiW/LZO/CeO2 RABiTS substrates, and the resulting multifilamentary samples characterised by microscopy and scanning Hall probe measurements. The prospects for future inkjet-printed low AC loss coated conductors are discussed, including control of interfilamentary resistivity and bridging, transposed filamentary structures and stabilisation material.

This paper reports the successful application of ink-jet printing to the deposition of both continuous coatings and multi-filamentary structures of YBCO. Stable inks have been prepared using both the established TFA-MOD route and novel fluorine-free precursors with appropriate rheological properties for ink-jet printing. Continuous and well textured coatings with lengths exceeding 100 m and a thickness of 0.5 mu m have been deposited by electromagnetic ink-jet printing from TFA precursors on LZO-buffered Ni-W substrates and samples have achieved a J(c) around 1.5 MA cm(-2) ( self-field, 77 K). On single crystal substrates, continuous coatings and multi-filamentary structures have been deposited using piezoelectric ink-jet printing both from TFA- and water-based precursors, achieving J(c) values up to 3 MA cm(-2).

The interest in functional ceramic coatings based on low cost and flexible manufacturing has been heightened by the effectiveness shown by chemical solution deposition of metal-organic salts, usually based on the use of spin coating, dip coating, or slot die coating techniques prior to thermal treatment to achieve decomposition of the starting salts. The possibility of implementing effective drop on demand systems in the manufacturing process allows a more efficient way to apply the precursor solution homogeneously onto the substrate, thus, enabling control of thickness of the ceramic coating, by controlling the drop size and the pitch of the printing pattern, among other manufacturing advantages such as control of solvent evaporation. In the present work, the authors report on their experiments concerning ink jet coating of functional complex ceramics for La0.7Sr0.3MnO3 and YBa2Cu3O7-x layers and patterns over single crystal and polycrystalline substrates using an electromagnetic system and a single nozzle piezoelectric dispenser. Characterization of rheological properties of the developed ink and of the resulting coating by optical microscopy, x-ray diffraction, scanning electron microscopy, and magnetic behavior are reported. (C) 2011 Society for Imaging Science and Technology [DOI: 10.2352/J.ImagingSci.Technol.2011.55.4.040304]

Chemical solution deposition (CSD) was used to grow high-quality (100) oriented films of SrTiO3 (STO) on CSD CaTiO3 (CTO), Ba0.1Ca0.9TiO3 (BCT) and STO seed and template layers. These template films bridge the lattice misfit between STO and the nickel–tungsten (NiW) substrate, assisting in dense growth of textured STO. Additional niobium (Nb) doping of the STO buffer layer reduces oxygen diffusion which is necessary to avoid undesired oxidation of the NiW. The investigated templates offer suitable alternatives to established standard buffer systems like La2Zr2O7 (LZO) and CeO2 for coated conductors.

Due to increasing global competition, growing pressure of time and prices as well as the individualization of products, enterprises are obliged to implement structural and process organizations which are flexible and to optimise them permanently. As a result, flexible information systems which on the one hand support new forms of organization and on the other hand can be adapted efficiently by trained personnel are required. The purpose of this paper is to present a concept for a user-friendly production control system that is based on a model based toolbox.

For the determination of superconducting properties of HTS wires and tapes an exact analysis of the cross section of the silver sheath and the filaments is essential. The normal procedure for this analysis is to perform image analysis on optical microscopic or SEM images of the conductor cross section. These methods are very time consuming and reflect only a snapshot of the average cross section of the wires/tapes, because the detection is only local. To overcome these difficulties an easy method has been developed to determine cross section in a chemical way via titration. The obtained data reflect an average silver and filament cross section over variable conductor lengths. In addition the porosity of the filaments can easily be calculated.

Six partners from five European countries are cooperating within a R&D BRITE EURAM project named SHIFT (superconducting high-T/sub c/ coils for high field technologies). The objective of this 3-year project is to develop basic technologies for manufacturing magnets producing high fields operating in the temperature range 20-30 K: HTS wires, coils based on bulk parts, coil structures and cooling system. The potential applications are pulsed magnets for power quality SMES and DC magnets for MRI, instrumentation and laboratory use. Specifications and designs of SMES for the voltage sags smoothing application have been performed and will be presented together with SMES designs for flicker mitigation. Main deliverables are the realization of a 6 Tesla demonstration coil cooled by closed cycle refrigeration and the design of a SMES coil for power quality applications. Target performances, conductors, test coil developments and designs are discussed in this paper.

The invention relates to a method for coating shaped bodies made of a superconducting material based on (Y/SE)BaCuO. The invention is characterized in that a coating consisting of a coating material is applied to at least one part of a surface of the shaped body, whereby the coating material at least partially melts at a lower temperature than that of the material of the shaped body and/or is flowable at a lower temperature than that of said material. The shaped body with the applied coating material is heated to a temperature at which the material of the shaped body does not yet melt and/or is not yet flowable, however at which the coating material is at least partially melted thereon and/or is in a flowable state. In addition, at least one part of the area of the shaped body located near the surface is modified at said temperature and/or during a successive cooling, and the shaped body treated in such a manner is enriched with oxygen during cooling and/or during a successive heat treatment, whereby the modification contributes to the increase in remanent induction and/or to the critical current density of the shaped body enriched with oxygen. The invention also relates to a shaped body made of a superconducting material which is based on (Y/SE)BaCuO and which can be obtained by using the above-mentioned method. Said superconducting material contains at least one rare-earth element selected from the group of Y, La, Ce, Pr, Nd, Eu, Gd, Tb, Dy, Ho, Er, Tm, Yb and Lu and comprises a maximal value of remenant induction of at least 1100 mT at 77 K and 0 T.

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