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Large transport critical currents in dense Fe- and Ni-clad MgB2 superconducting tapes

HongLi Suo·Concetta Beneduce·Marc Dhalle·Nicolas Musolino·Jean-Yves Genoud·Rene Flukiger
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Abstract

We report on the preparation of dense monofilamentary MgB2/Ni and MgB2/Fe tapes with high critical current densities. In annealed MgB2/Ni tapes, we obtained transport critical current densities as high as 2.3*105 A/cm2 at 4.2 K and 1.5 T, and for MgB2/Fe tapes 104 A/cm2 at 4.2 K and 6.5 T. To the best of our knowledge, these are the highest transport jc values at 4.2 K reported for MgB2 based tapes so far. An extrapolation to zero field of the MgB2/Fe data gives a critical current value of ~ 1 MA/cm2, corresponding to an critical current value well above 1000 A. The high jc values obtained after annealing are a consequence of sintering densification and grain reconnection. Fe does not react with MgB2 and is thus an excellent sheath material candidate for tapes with self-field jc values at 4.2 K in excess of 1 MA/cm2.

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HongLi Suo, Concetta Beneduce, Marc Dhalle, Nicolas Musolino, Jean-Yves Genoud, Rene Flukiger. 2001-06-18. Large transport critical currents in dense Fe- and Ni-clad MgB2 superconducting tapes. https://doi.org/10.1063/1.1415349

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