Dresden 2011 – scientific programme
Parts | Days | Selection | Search | Updates | Downloads | Help
TT: Fachverband Tiefe Temperaturen
TT 10: Poster Session: Superconductivity
TT 10.7: Poster
Monday, March 14, 2011, 14:00–18:00, P4
Mechanically alloyed in-situ MgB2: Aspects of powder preparation towards an industrial scale wire preparation — •Marko Herrmann1, Wolfgang Häßler1, Christian Rodig1, Margitta Schubert1, Ania Kario1, Konstantin Nenkov1, Juliane Scheiter1, Ludwig Schmolinga2, André Aubele3, Bernd Sailer3, Klaus Schlenga3, Bernhard Holzapfel1, and Ludwig Schultz1 — 1IFW Dresden, Institute for Metallic Materials, Dresden, Germany — 2Bruker HTS GmbH, Alzenau, Germany — 3Bruker EAS GmbH, Hanau, Germany
During the powder-in-tube preparation using sheath materials, e.g. Monel or CuNi alloys, it is necessary to recover the metallic sheath in order to reduce work hardening and allow for further deformation. In combination with a mechanically alloyed in-situ precursor this intermediate heat treatment is a sensitive processing step. Due to the high reactivity of the nanocrystalline precursor an unintended MgB2 formation starting at around 350∘C is observed. With ongoing phase formation the hardness of the precursor is increasing and therefore limiting the deformability of the wire composite.
In order to allow for a reliable wire preparation this paper concentrates on the characterization of the reactivity of mechanically alloyed precursor powders using x-ray diffraction studies with subsequent Rietveld analysis. Experimental results of transport measurements and microstructural investigations on MgB2 bulk samples, wires and tapes prepared with precursor powders of different processing, e.g. variation of milling energy and carbon addition, will be discussed.