FP6 priority
1.1.3   Nanotechnologies and Nanosciences, Knowledge-based Multifunctional Materials and New Production Processes and Devices
1.3.2
Title of the proposal

Low loss Bi-2223 and high current MgB2 superconductors
Institute
Slovak Academy of Sciences, Institute of Electrical Enginnering
Dubravska cesta 9, 842 39 Bratislava, Slovak Republic
www.elu.sav.sk
Contact
Name:
Pavol KOVAC, Ing., DrSc.
Phone:
+421 2 5477 5823-2841
E-mail:
elekkova@savba.sk


Research subject for a potential FP6 project

Objectives:
  • Improvement in transport current density and loss reduction of Bi-2223 tapes with resistive barrier for AC applications
  • Increase of transport currents in single- and multi-core MgB2 wires and tapes
    Bi-2223: To meet the application requirements (reach acceptable current densities), the diffusion of oxygen through the barrier and reactivity of barrier with BSCCO study is still substantial to find the most suitable material for resistive barrier. Implementation of resistive barrier has a direct effect also on mechanical properties of BSCCO/Ag composites, which is important from the point of filament twisting and critical current degradation by torsion, tension and/or bending stress.
    MgB2: Discovery of new superconducting compound MgB2 in 2001 with critical temperature close to 40K has inspired to develop composite wires and tapes involving this material. The absence of weak-link nature in MgB2 is very promising regarding possible engineering applications. Several kinds of wires using in situ (Mg+2B) and ex situ (MgB2) methods were prepared by PIT technique. Ic is strongly influenced by the fill factor, i.e.: MgB2 vs. sheath ratio, and by the mechanical properties of the sheath material.
    Future work will be focussed on the improvements in Jc in the form of single- and multi-filamentary composite wires/tapes. To meet these requirements, the proper composite materials, suitable deformation techniques and optimal heat treatments conditions should be find.


    • Recent international cooperation of the research team

    University of Twente, Enschede, The Netherlands; High Pressure Research Center Warszaw, Poland; Institute of Experimental Physics of Technical University Wien, Austria; Nordic Superconductors Technologies, Copenhagen, Denmark; Merck KGaA, Darmstadt, Germany;Allgemeine Gold- und Silber AG, Pforzhiem, Germany; Oxford Magnet Technology Ltd., Oxford, England; Institute for Product Development, Copenhagen, Denmark; National Institute for Nuclear Physics, Genova, Italy; Blacket Laboratory, Imperial College, London, England; University of Tampere, Tampere, Finland


    Proposer´s relevant publications related to the research subject

    P. Kovac, C. J. Eastell, W. Pachla, I. Husek, H. Marciniak, C. R. M. Grovenor and M. J. Goringe, Physica C 292 (1997) 322 – 338
    P. Kovac, I. Husek, and L. Kopera, Superconductor Sci and Technology (1997) 10 982-986
    P. Kovac, I. Husek, A. Rosova, and W. Pachla, Physica C 312 (1999) 179-190
    P. Kovac, T. Melisek, A. Kasztler, W. Pachla, J. Pitel, R. Diduszko and H. Kirchmayr, (2000) IOP Inst. Phys. Conf. Ser. No 167 535-538
    J. Pitel, P. Kovac and I. Husek, Physica C 330 (2000) 130-140
    J. Lehtonen, J. Paasi, A. Korpela, J. Pitel and P. Kovac, Adv. Cryog. Eng. 46 (2000) 839-846
    P. Kovac, I. Husek, T. Melisek, W. Pachla, R. Diduszko, Physica C 349 (2001) 179-188
    P. Kovac, I. Husek, W. Pachla, M. Diantoro, G. Bonfait, K. Frõhlich, L. Kopera, R. Diduszko and A. Presz, Superconductor Sci and Technology (2001) 14 966-972
    P. Kovac, I. Husek, T. Melisek, A. Metz, H.J.N. van Eck and B. ten Haken, Superconductor Sci and Technology (2002) 15 624-629