Progress in Superconductivity and Cryogenics (한국초전도ㆍ저온공학회논문지)

The Korean Society of Superconductivity and Cryogenics (한국초전도저온학회)
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Superconducting properties of MgB2 superconductors in-situ processed using various boron powder mixtures

  • Kang, M.O. (Advanced 3D Printing Technology Research Division, Korea Atomic Energy Research Institute) ;
  • Joo, J. (School of Advanced Material Science and Engineering, Sungkyunkwan University) ;
  • Jun, B.H. (Advanced 3D Printing Technology Research Division, Korea Atomic Energy Research Institute) ;
  • Kim, C.J. (Advanced 3D Printing Technology Research Division, Korea Atomic Energy Research Institute)
  • Received : 2021.06.29
  • Accepted : 2021.07.15
  • Published : 2021.09.30
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Abstract

In this study, the effect of the size of B powder on the critical current density (Jc) of MgB2 prepared by an in situ reaction process was investigated. Various combinations of B powders were made using a micron B, ball-milled B and nano B powders. Micron B powder was reduced by ball milling and the milled B powder was mixed with the micron B or nano B powder. The mixing ratios of the milled B and micron or nano B were 100:0, 50:50 and 0:100. Non-milled micron B powder was also mixed with nano powder in the same ratios. Pellets of (2B+Mg) prepared with various B mixing ratios were heat-treated to form MgB2. Tc of MgB2 decreased slightly when the milled B was used, whereas the Jc of MgB2 increased with increasing amount of the milled B or the nano powder. The used of the milled B and nano B power promoted the formation MgB2 during heat treatment. In addition to the enhanced formation of MgB2, the use of the powders reduced the grain size of MgB2. The use of the milled and nano B powder increased the Jc of MgB2. The highest Jc was achieved when 100% nano B powder was used. The Jc enhancement is attributed to the high volume fraction of the superconducting phase (MgB2) and the large grain boundaries, which induces the flux pinning at the magnetic fields.

Keywords

Acknowledgement

This work was supported by the National Research Foundation Grant(NRF-2020M2D8A2047959) funded from Ministry of Science and ICT(MSIT) of Republic of Korea.

References

  1. J. Nagamatsu, N. Nakagawa, T. Muranaka, Y. Zenitani, and J. Akimitsu, "Superconductivity at 39 K in magnesium diboride," Nature, vol. 410, pp. 63-64, 2001. https://doi.org/10.1038/35065039
  2. W. Goldacker, S. I. Schlachter, B. Obst, and M. Eisterer, "In situ MgB2 round wires with improved properties," Supercond. Sci. Technol., vol. 17, pp. S490-S495, 2004. https://doi.org/10.1088/0953-2048/17/9/006
  3. C. -J. Kim, J. H. Yi, B. -H. Jun, B. Y. You, S. -D. Park, and K. -N. Choo, "Reaction-induced pore formation and superconductivity in in situ processed MgB2 superconductors," Physica C, vol. 502, pp. 4-9, 2014. https://doi.org/10.1016/j.physc.2014.04.006
  4. M. O. Kang, J. Joo, B. -H. Jun, S. -D. Park, C. S. Kim, and C. -J. Kim, "Effect of boron milling on phase formation and the critical current density of MgB2 bulk superconductors," Prog. Supercond. Crygen. vol. 21, pp. 18-24. 2019.
  5. A. V. Pan, S. Zhou, H. Liu, and S. Dou, "Properties of superconducting MgB2 wires: in situ versus ex situ reaction technique," Supercond. Sci. Technol., vol. 16, pp. 639-644, 2003. https://doi.org/10.1088/0953-2048/16/5/317
  6. C. U. Jung, M. S. Park, M. S. Kim, J. H. Choi, W. N. Kang, H. P. Kim, and S. I. Lee, "High-pressure sintering of highly dense MgB2 and its unique pinning properties," Surr. Appl. Phys., vol. 1, pp. 327-331, 2001.
  7. B. A. Glowacki, M. Majoros, M. Vickers, J. E. Evetts, Y. Shi, and I. Mcdougall. "Superconductivity of powder-in-tube MgB2 wires," Supercond. Sci. Technol., vol. 14, pp. 193-199, 2001. https://doi.org/10.1088/0953-2048/14/4/304
  8. A. Tampieri, G. Celotti, S. Sprio, R. Caciuffo, and D. Rinaldi, "Study of the sintering behavior of MgB2 superconductor during hot-pressing," Physica C, vol. 400, pp. 97-104, 2004. https://doi.org/10.1016/S0921-4534(03)01310-8
  9. E. Martinez, L. A. Angurel, and R. Navarro, "Study of Ag and Cu/MgB2 powder-in-tube composite wires fabricated by In situ reaction at low temperature," Supercond. Sci. Technol., vol. 15, pp. 1043-1047, 2002. https://doi.org/10.1088/0953-2048/15/7/309
  10. B. H. Jun and C. J. Kim. "The effect of heat-treatment temperature on the superconducting properties of malic acid-doped MgB2/Fe wire," Supercond. Sci. Technol., vol. 20, pp. 980-985, 2007. https://doi.org/10.1088/0953-2048/20/10/015
  11. J. H. Kim, S. X. Dou, J. L. Wang, D. Q. Shi, X. Xu, M. S. A. Hossain, W. K. Yeoh, S. Choi, and T. Kiyoshi, "The effects of sintering temperature on superconductivity in MgB2/Fe wires," Supercond. Sci. Technol., vol. 20, pp. 448-451, 2007. https://doi.org/10.1088/0953-2048/20/5/007
  12. A. Yamamoto, J. I. Shimoyama, S. Ueda, Y. Katsura, S. Horii, and K. Kishio, "Improved critical current properties observed in MgB2 bulk synthesized by low-temperature solid-state reaction," Supercond. Sci. Tehchnol., vol. 18, pp. 116-121, 2004.
  13. G. S. Brady and H. R. Clauser, Materials Handbook, 12th ed., vol. 15, pp. 104-105, 1956.
  14. W. Goldacker, S. I. Schlachter, B. Obst, and M. Eisterer, "In-situ MgB2 round wires with improved properties," Supercond. Sci. Technol., vol. 17, pp. S490-495, 2004. https://doi.org/10.1088/0953-2048/17/9/006
  15. B. -H. Jun, N. -K. Kim, K. S. Tan, and C. -J. Kim, "Enhanced critical current properties of in situ processed MgB2 wires using milled boron powder and low temperature solid-state reaction," J. Alloys compd., vol. 492, pp. 446-451, 2010. https://doi.org/10.1016/j.jallcom.2009.11.134
  16. S. Sugino, A. Yamamoto, J. Shimoyama, and K. Kishio, "Enhanced trapped field in MgB2 bulk magnets by tuning grain boundary pinning through milling," Supercond. Sci. Technol., vol. 28, pp. 055016, 2015. https://doi.org/10.1088/0953-2048/28/5/055016
  17. B. -H. Jun, S. -D. Park, and C. -J. Kim, "Refinement and carbon incorporation effects on the superconducting properties of MgB2 through wet milling process of low purity boron powder," J. Alloys compd., vol. 535, pp. 27-32, 2012. https://doi.org/10.1016/j.jallcom.2012.04.030
  18. C. P. Bean, "Magnetization of High-Field Superconductors," Rev. Mod. Phys., vol. 36, pp.31-39, 1964. https://doi.org/10.1103/RevModPhys.36.31
  19. J. H. Yi, K. T. Kim, B.-H. Jun, J. M. Sohn, B. G. Kim, J. Joo, and C.-J. Kim, "Pore formation in 'in situ' processed MgB2 superconductors," Physica C, vol. 469, no. 15-20, pp. 1192-1195, 2009. https://doi.org/10.1016/j.physc.2009.05.190
  20. D. N. Kim, B.-H. Jun, S.-D. Park, C.-J. Kim, and H. W. Park, "Effects of the size of Mg powder on the formation of MgB2 and the superconducting properties," Prog. Supercond. Crygen., vol. 18, pp. 9-14, 2016. https://doi.org/10.9714/psac.2016.18.4.009
  21. S. H. Kim, W. N. Kang, B.-H. Jun, Y. J. Lee, and C.-J. Kim "Enhanced critical current density of in situ processed MgB2 bulk superconductors with MgB4 additions," Prog. Supercond. Crygen. vol. 19, pp. 36-41, 2017. https://doi.org/10.9714/psac.2017.19.1.036
  22. P. Scherrer, "Bestimmung der Grosse und der inneren Struktur von Kolloidteilchen mittels Rontgenstrahlen," Nachr. Ges. Wiss. Gottingen, vol. 26, pp 98-100, 1918.