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Improved Current Densities in MgB2 By Liquid-Assisted Sintering

S. K. Chen·Z. Lockman·M. Wei·B. A. Glowacki·J. L. MacManus-Driscoll
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Abstract

Polycrystalline MgB2 samples with GaN additions were prepared by reaction of Mg, B, and GaN powders. The presence of Ga leads to a low melting eutectic phase which allowed liquid phase sintering and produces plate-like grains. For low-level GaN additions (5% at. % or less), the critical transition temperature, Tc, remained unchanged and in 1T magnetic field, the critical current density, Jc was enhanced by a factor of 2 and 10, for temperatures of \~5K and 20K, respectively. The values obtained are approaching those of hot isostatically pressed samples.

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S. K. Chen, Z. Lockman, M. Wei, B. A. Glowacki, J. L. MacManus-Driscoll. 2005-04-29. Improved Current Densities in MgB2 By Liquid-Assisted Sintering. https://doi.org/10.1063/1.1947374

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