Korean Journal of Materials Research (한국재료학회지)

Materials Research Society of Korea (한국재료학회)
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Effect of Low-Temperature Sintering on Electrical Properties and Aging Behavior of ZVMNBCD Varistor Ceramics

  • Nahm, Choon-Woo (Department of Electrical Engineering, Dongeui University)
  • Received : 2020.07.23
  • Accepted : 2020.09.14
  • Published : 2020.10.27
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Abstract

This paper focuses on the electrical properties and stability against DC accelerated aging stress of ZnO-V2O5-MnO2-Nb2O5-Bi2O3-Co3O4-Dy2O3 (ZVMNBCD) varistor ceramics sintered at 850 - 925 ℃. With the increase of sintering temperature, the average grain size increases from 4.4 to 11.8 mm, and the density of the sintered pellets decreases from 5.53 to 5.40 g/㎤ due to the volatility of V2O5, which has a low melting point. The breakdown field abruptly decreases from 8016 to 1,715 V/cm with the increase of the sintering temperature. The maximum non-ohmic coefficient (59) is obtained when the sample is sintered at 875 ℃. The samples sintered at below 900 ℃ exhibit a relatively low leakage current, less than 60 mA/㎠. The apparent dielectric constant increases due to the increase of the average grain size with the increase of the sintering temperature. The change tendency of dissipation factor at 1 kHz according to the sintering temperature coincides with the tendency of the leakage current. In terms of stability, the samples sintered at 900 ℃ exhibit both high non-ohmic coefficient (45) and excellent stability, 0.8% in 𝚫EB/EB and -0.7 % in 𝚫α/α after application of DC accelerated aging stress (0.85 EB/85 ℃/24 h).

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References

  1. M. Matsuoka, Jpn. J. Appl. Phys., 10, 736 (1971). https://doi.org/10.1143/JJAP.10.736
  2. L. M. Levinson and H. R. Philipp, Am. Ceram. Soc. Bull., 65, 639 (1986).
  3. K. Mukae, K. Tsuda, and I. Nagasawa, Jpn. J. Appl. Phys., 16, 1361 (1977). https://doi.org/10.1143/JJAP.16.1361
  4. D. R. Clarke, J. Am. Ceram. Soc., 82, 458 (1999).
  5. T. K. Gupta, J. Am. Ceram. Soc., 73, 1817 (1990). https://doi.org/10.1111/j.1151-2916.1990.tb05232.x
  6. C.-W. Nahm, Mater. Lett., 47, 182 (2001). https://doi.org/10.1016/S0167-577X(00)00262-7
  7. J.-K. Tsai and T.-B. Wu, J. Appl. Phys., 76, 4817 (1994). https://doi.org/10.1063/1.357254
  8. J.-K. Tsai and T.-B. Wu, Mater. Lett., 26, 199 (1996). https://doi.org/10.1016/0167-577X(95)00217-0
  9. C. T. Kuo, C. S. Chen and I.-N. Lin, J. Am. Ceram. Soc., 81, 2942 (1998). https://doi.org/10.1111/j.1151-2916.1998.tb02717.x
  10. H.-H. Hng and K. M. Knowles, J. Am. Ceram. Soc., 83, 2455 (2000). https://doi.org/10.1111/j.1151-2916.2000.tb01576.x
  11. H.-H. Hng and P. L. Chan, Mater. Chem. Phys., 75, 61 (2002). https://doi.org/10.1016/S0254-0584(02)00031-7
  12. H.-H. Hng and L. Halim, Mater. Lett., 57, 1411(2003). https://doi.org/10.1016/S0167-577X(02)00999-0
  13. C.-W. Nahm, J. Mater. Sci.: Mater. Electron., 21, 540 (2010). https://doi.org/10.1007/s10854-009-9954-8
  14. C.-W. Nahm, J. Mater. Sci.: Mater. Electron., 22, 444 (2011). https://doi.org/10.1007/s10854-010-0157-0
  15. C.-W. Nahm, J. Mater. Sci.: Mater. Electron., 23, 457 (2012). https://doi.org/10.1007/s10854-011-0512-9
  16. J. C. Wurst and J. A. Nelson, J. Am. Ceram. Soc., 55,109 (1972). https://doi.org/10.1111/j.1151-2916.1972.tb11224.x