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Magnetic characterization of sintered MgB2 samples: effect of the substitution or doping with Li, Al and Si

M. R. Cimberle·M. Novak·P. Manfrinetti·A. Palenzona
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Abstract

Powdered and sintered MgB2 samples have been characterized through magnetic measurements performed from T = 5 K up to few degrees above the transition temperature of about 39 K. We found that the sintered samples behave as well-connected bodies, showing no trace of granularity. In order to obtain the critical current density value Jc the Critical State Model has been therefore employed in a straightforward way. With the aim either to decrease the electron mean free path or to increase its Jc we have attempted to introduce defects in the MgB2 structure by different procedures: substitution of Lithium on the Magnesium site and doping of the precursor Boron powders with Aluminum and Silicon. The best result in terms of Jc has been achieved by Silicon doping that, moreover, does not significantly affect the transition temperature.

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M. R. Cimberle, M. Novak, P. Manfrinetti, A. Palenzona. 2001-06-07. Magnetic characterization of sintered MgB2 samples: effect of the substitution or doping with Li, Al and Si. https://doi.org/10.1088/0953-2048%2F15%2F1%2F308

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