Progress in Superconductivity

The Korean Superconductivity Society (한국초전도학회)
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Mechanical Alloying and Combined Process of in-situ and ex-situ to Fabricate the ex-situ C-doped $MgB_2$ Wire

기계적 합금화 및 in-situ와 ex-situ의 혼합공정을 통한 C 도핑된 ex-situ $MgB_2$ 선재 제조

  • Hwang, Soo-Min (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Lee, Chang-Min (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Lim, Jun-Hyung (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Choi, Jun-Hyuk (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Park, Jin-Hyun (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Joo, Jin-Ho (School of Advanced Materials Science and Engineering, Sungkyunkwan University) ;
  • Jun, Byung-Hyuk (Neutron Science Division, Korea Atomic Energy Research Institute(KAERI)) ;
  • Kim, Chan-Joong (Neutron Science Division, Korea Atomic Energy Research Institute(KAERI))
  • Published : 2009.04.30
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Abstract

We successfully fabricated C-doped ex-situ $MgB_2$ wires using two different methods such as mechanical alloying(MA) and combined process(CP) of in-situ and ex-situ. In the MA, the precursor powder was prepared with a mixture of $MgB_2$ and 1 at% C powders by planetary ball milling for 0-100 h. In the CP, on the other hand, C-doped $MgB_2$ powder was prepared with Mg, B, and C powders by in-situ process via compaction, sintering, and crushing. The powders prepared by two methods were loaded into Fe tube and then the assemblages were drawn by a conventional powder-in-tube technique. The MA treatment of C-added $MgB_2$ decreased the particles/grains size and resulted in C-doping into $MgB_2$ after sintering, improving the critical current density($J_c$) in high external magnetic field. For the C-doped $MgB_2$ wire by MA for 25 h, the $J_c$ was $4.1{\times}10^3A/cm^2$ at 5 K and 6.4 T, which was 5.9 times higher than that of pure and untreated $MgB_2$ wire. The CP also provided C-doping into $MgB_2$ and improved the $J_c$ in high magnetic field; the C-doped $MgB_2$ wire fabricated by CP exhibited a $J_c$ being 2.3 times higher than that of the ex-situ wire used commercial $MgB_2$ powder at 5 K and 6.0 T($2.7{\times}10^3A/cm^2\;vs.\;1.2{\times}10^3A/cm^2$).

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References

  1. J. Nagamatsu, N. Nakagawa, T. Muranaka, Y. Zenitani, J. Akimitsu, “Superconductivity at 39 K in magnesium diaboride,” Nature, 410, 63-64 (2001). https://doi.org/10.1038/35065039
  2. Cristina Buzea and Tsutomu Yamashita, “Review of the superconducting properties of $MgB_2$,” Supercond. Sci. Technol., 14, 115-146 (2001). https://doi.org/10.1088/0953-2048/14/11/201
  3. P. Kovac et al., “Improvement of the current carrying capability of ex situ $MgB_2$ wires by normal particle additions,” Supercond. Sci. Technol., 17, 1225-1230 (2004). https://doi.org/10.1088/0953-2048/17/11/001
  4. P. Kovac et al., “Transport current improvements of in situ $MgB_2$ tapes by the addition of carbon nanotubes, silicon carbide or graphite,” Supercond. Sci. Technol., 20, 105-111 (2007). https://doi.org/10.1088/0953-2048/20/1/019
  5. H. Fujii, K. Togano and K. Ozawa, “Grain coupling and critical current density in Fe-sheathed carbonsubstituted $MgB_2$ tapes fabricated through an ex situ process using chemically treated powder,” Supercond. Sci. Technol., 21, 095018 (2008). https://doi.org/10.1088/0953-2048/21/9/095018
  6. M. Herrmann et al., “The effect of reactive nanostructured carbon on the superconducting properties of mechanically alloyed $MgB_2$,” Supercond. Sci. Technol., 20, 1108-1114 (2007). https://doi.org/10.1088/0953-2048/20/12/004
  7. M. Maeda et al., “Fabrication of highly dense $MgB_2$ bulk at ambient pressure,” Supercond.. Sci. Technol., 21, 032004 (2008). https://doi.org/10.1088/0953-2048/21/3/032004
  8. Valeria Braccini et al., “Improvement of Magnetic Field Behavior of Ex-Situ Processed Magnesium Diboride Tapes,” IEEE Trans. Appl. Supercond., 17, 2766-2769 (2007)
  9. HongLi Suo et al., “Large transport critical currents in dense Fe- and Ni-clad $MgB_2$ superconducting tapes,” Appl. Phys. Lett., 79, 3116-3118 (2001). https://doi.org/10.1063/1.1415349
  10. W. K. Yeoh and S. X. Dou, “Enhancement of $H_{c2}$ and $J_c$ by carbon-based chemical doping,” Physic C, 456, 170-179 (2007). https://doi.org/10.1016/j.physc.2007.01.024
  11. C. Suryanarayana, “Mechanical alloying and milling,” Prog. Mater. Sci., 46, 1-184 (2001). https://doi.org/10.1016/S0079-6425(99)00010-9
  12. W HaBler et al., “$MgB_2$ bulk and tapes prepared by mechanical alloying: influence of the boron precursor powder,” Supercond. Sci. Technol., 19, 512-520 (2006). https://doi.org/10.1088/0953-2048/19/6/018
  13. P Lezza, R Gladyshevskii, H L Suo and R Flükiger, “Quantitative study of the inhomogeneous distribution of phases in Fe-sheathed ex situ $MgB_2$ tapes,” Supercond. Sci. Technol., 18, 753-757 (2005). https://doi.org/10.1088/0953-2048/18/5/030
  14. X. Xu et al., “Phase transformation and superconducting properties of $MgB_2$ using ball-milled low purity boron,” J. Appl. Phys, 103, 023912 (2008). https://doi.org/10.1063/1.2832752
  15. T. Takenobu, T. Ito, Dam Hieu Chi, K. Prassides and Y. Iwasa, “Intralayer carbon substitution in the $MgB_2$ superconductor,” Phys. Rev. B, 64, 134513 (2001). https://doi.org/10.1103/PhysRevB.64.134513
  16. V.P.S. Awana et al., “Role of carbon in enhancing the performance of $MgB_2$ superconductor,” Physica C, 467, 67-72 (2007). https://doi.org/10.1016/j.physc.2007.08.011
  17. B. J. Senkowicz et al., “Improved upper critical field in bulk-form magnesium diboride by mechanical alloying with carbon,” Appl. Phys. Lett., 86, 202502 (2005). https://doi.org/10.1063/1.1920428
  18. B. J. Senkowicz et al., “Understanding the route to high critical current density in mechanically alloyed Mg$(B_{1-x}C_{x})_2$,” Supercond. Sci. Technol., 20, 650-657 (2007). https://doi.org/10.1088/0953-2048/20/7/011
  19. S. Soltanian, J. Horvat, X.L. Wang, P. Munroe, S.X. Dou, “Effect of nano-carbon particle doping on the flux pinning properties of $MgB_2$ superconductor,” Physica C, 390, 185-190 (2003). https://doi.org/10.1016/S0921-4534(03)00960-2
  20. J. H. Kim, S. X. Dou, D.Q. Shi, M. Rindfleisch and Tomsic, “Study of MgO formation and structural defects in in situ processed $MgB_2$/Fe wires,” Supercond. Sci. Technol., 20, 1026-1031 (2007). https://doi.org/10.1088/0953-2048/20/10/023
  21. S. K. Chen, Z. Lockman, M. Wei, B. A. Glowacki, and J. L. MacManus-Driscoll, “Improved current densities in $MgB_2$ by liquid-assisted sintering,” Appl. Phys. Lett., 86, 242501 (2005). https://doi.org/10.1063/1.1947374