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Enhancement of in-field Jc in MgB2/Fe wire using single and multi-walled nanotubes

J. H. Kim·W. K. Yeoh·M. J. Qin·X. Xu·S. X. Dou·P. Munroe·H. Kumakura·T. Nakane·C. H. Jiang
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Abstract

We investigated the doping effects of SWCNTs and MWCNTs on the Tc, lattice parameters, Jc(B), microstructure, and Hc2 of MgB2/Fe wire. These effects systematically showed the following sequence for Tc and the a-axis: the SWCNT doped wire < the MWshortCNT doped wire < the MWlongCNT doped wire < un-doped wire, while Jc(B) followed the sequence of the SWCNT doped wire > the MWshortCNT doped wire > the MWlongCNT doped wire > un-doped wire. A dominating mechanism behind all these findings is the level of C substitution for B in the lattice. The best Jc(B) and Hc2 were obtained on SWCNT doped wire because the level of C substitution for B in this wire is higher than all others.

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J. H. Kim, W. K. Yeoh, M. J. Qin, X. Xu, S. X. Dou, P. Munroe, H. Kumakura, T. Nakane, C. H. Jiang. 2006-07-21. Enhancement of in-field Jc in MgB2/Fe wire using single and multi-walled nanotubes. https://doi.org/10.1063/1.2355467

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