Higher borides and oxygen-enriched Mg-B-O inclusions as possible pinning centers in nanostructural magnesium diboride and the influence of additives on their formation

Tatiana Prikhna; Wolfgang Gawalek; Yaroslav Savchuk; Vasiliy Tkach; Nikolay Danilenko; Michael Wendt; Jan Dellith; Harold Weber; Michael Eisterer; Viktor Moshchil; Nina Sergienko; Artem Kozyrev; Peter Nagorny; Andrey Shapovalov; Vladimir Melnikov; Sergey Dub; Doris Litzkendorf; Tobias Habisreuther; Christa Schmidt; Athanasios Mamalis; Vladimir Sokolovsky; Vladimir Sverdun; Fridrich Karau; Alexandra Starostina

doi:10.1016/j.physc.2010.02.064

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arXiv · 1001.1904

Higher borides and oxygen-enriched Mg-B-O inclusions as possible pinning centers in nanostructural magnesium diboride and the influence of additives on their formation

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Abstract

The study of high pressure (2 GPa) synthesized MgB2-based materials allows us to conclude that higher borides (with near MgB12 stoichiometry) and oxygen-enriched Mg-B-O inclusions can be pinning centers in nanostructural magnesium diboride matrix (with average grain sizes of 15-37 nm). It has been established that additions of Ti or SiC as well as manufacturing temperature can affect the size, amount and distribution of these inclusions in the material structure and thus, influence critical current density. The superconducting behavior of materials with near MgB12 stoichiometry of matrix is discussed.

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Tatiana Prikhna, Wolfgang Gawalek, Yaroslav Savchuk, Vasiliy Tkach, Nikolay Danilenko, Michael Wendt, Jan Dellith, Harold Weber, Michael Eisterer, Viktor Moshchil, Nina Sergienko, Artem Kozyrev, Peter Nagorny, Andrey Shapovalov, Vladimir Melnikov, Sergey Dub, Doris Litzkendorf, Tobias Habisreuther, Christa Schmidt, Athanasios Mamalis, Vladimir Sokolovsky, Vladimir Sverdun, Fridrich Karau, Alexandra Starostina. 2010-01-12. Higher borides and oxygen-enriched Mg-B-O inclusions as possible pinning centers in nanostructural magnesium diboride and the influence of additives on their formation. https://doi.org/10.1016/j.physc.2010.02.064

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