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Influence of the Preparation Process on Microstructure, Critical Current Density and Tc of MgB2 Powder-In-Tube Wires

S. I. Schlachter·W. Goldacker·J. Reiner·S. Zimmer·B. Liu·B. Obst
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Abstract

MgB2 wires and tapes suffer from a limitation of the transport current densities, especially at low field, due to an unsufficient thermal stabilization caused by hot spots from a non-homogeneous microstructure, the presence of secondary phases and voids. For the preparation of MgB2 wires and tapes two different precursor routes, using MgB2 (ex-situ process) or Mg + B (in-situ process) are applied. The in-situ approach allows variation of many parameters in the wire preparation and the improvement of this approach is the central topic of this paper. We present an improved in-situ approach, the characterization of the filament microstructure, effects from stoichiometry and the corresponding superconducting properties. The transport current capability of such in-situ wires could be improved to the level of the reference ex-situ wires.

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S. I. Schlachter, W. Goldacker, J. Reiner, S. Zimmer, B. Liu, B. Obst. 2002-10-28. Influence of the Preparation Process on Microstructure, Critical Current Density and Tc of MgB2 Powder-In-Tube Wires. https://doi.org/10.1109/tasc.2003.812197

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