Record critical current density in bulk MgB.sub.2./sub. using carbon-coated amorphous boron with optimum sintering conditions

0477669 - FZÚ 2018 RIV GB eng C - Conference Paper (international conference)
Muralidhar, M. - Higuchi, M. - Diko, P. - Jirsa, Miloš - Murakami, M.
Record critical current density in bulk MgB₂ using carbon-coated amorphous boron with optimum sintering conditions.
Journal of Physics: Conference Series. Vol. 871. Bristol: IOP Publishing, 2017, s. 1-6, č. článku 012056. ISSN 1742-6588.
[International Symposium on Superconductivity /29./, ISS 2016. Tokyo (JP), 13.12.2016-15.12.2016]
Institutional support: RVO:68378271
Keywords : MgB₂ * bulk superconductors * microstructure * critical currents * carbon coated boron
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)

We report on the synthesis and characterization of a sintered bulk MgB2 material produced at an optimized sintering temperature with a varying content of carbon-encapsulated amorphous boron. A series of MgB2 bulks was prepared with 0%, 1.5%, 2.8%, 7.3%, 12% and 16.5% of carbon-encapsulated boron. In the samples with 12% of carbon-encapsulated boron, Mg and MgB2C2 formation was observed. Tc was around 38.4 K for the pure MgB2 and decreased with increasing carbon content up to 25 K for 16.5 % of carbon-encapsulated boron. The highest Jc values of 470 kA/cm2 and 310 kA/cm2, in the self-field and 1 T, respectively, were achieved at 20 K, in the MgB2 sample with 1.5% of carbon-encapsulated boron. It proved that the optimized sintering conditions together with the appropriate amount of the carbon-coated boron were able to bring critical current performance of bulk MgB2 material up to the level necessary for real technical applications.


Permanent Link: http://hdl.handle.net/11104/0273949