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http://dx.doi.org/10.3740/MRSK.2005.15.11.722

The Effect of Cobalt Oxide Addition on Electrical and Dielectic Stability of Zinc Oxide Varistors  

Nahm Choon-Woo (Department of Electrical Engineering, Dongeui University)
Yoo Dae-Hoon (Department of Electrical Engineering, Dongeui University)
Publication Information
Korean Journal of Materials Research / v.15, no.11, 2005 , pp. 722-729 More about this Journal
Abstract
The electrical and dielectric stability of zinc oxide-based varistors were investigated with the cobalt oxide contents in the range of $0.5\~5.0 mo\l%$. As cobalt oxide contents increased, the ceramic density increased in the range of $5.25\~5.55g/cm^3$ and the varistor voltage decreased in the range of $235.3\~86.0V$. The varistor with on addition of cobalt oxide $1.0 mol\%$ exhibited good nonlinearity. in which the nonlinear exponent is 66.6 and the leakage current is $1.2{\mu}A$. Furthermore, the varistors exhibited the highest electrical and dielectric stability, with $\%{\Delta}V_{1mA}=-1.9\%,\;\%{\Delta}{\alpha}=-10.5\%,\;\%{\Delta}I_L=+275.0\%,\;and\;\%{\Delta}tna{\delta}=+55.6\%$, under DC accelerated aging $0.95V_{1mA}/150^{\circ}C/24h$.
Keywords
cobalt oxide; varistor voltage; stability; DC accelerated aging stress;
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1 T. K. Gupta, J. Amer. Ceram. Soc., 73, 1817 (1990)   DOI
2 A. B. Alles and L. Burdick, J. Appl. Phys., 70, 6883 (1991)   DOI
3 Y. S. Lee and T. Y. Tseng, J Amer, Ceram. Soc., 75, 1636 (1992)   DOI
4 A. B. Alles, R. Puskas, G. Callahan and V. L. Burdick, J. Amer, Ceram. Soc., 76, 2098 (1993)   DOI   ScienceOn
5 H. H. Hng and K. M. Knowles. J. Mater. Sci., 37, 1143 (2002)   DOI   ScienceOn
6 J. C. Wurst and J. A. Nelson, J. Amer. Ceram. Soc., 97, 109 (1972)   DOI
7 C. W. Nahm and J. A. Park, J. Kor. Ceram. Soc., 41, 464 (2004)   과학기술학회마을   DOI
8 C. W. Nahm, Mater. Chem. Phys., 88, 318 (2004)   DOI   ScienceOn
9 C. W. Nahm, J. A. Park, B. C. Shin and I. S. Kim, J. Ceram. Inter., 30, 1009 (2004)   DOI   ScienceOn
10 C. W. Nahm, J. A. Park and M. J. Kim, J. Mater. Sci., 39, 307 (2004)   DOI   ScienceOn
11 C. W. Nahm and H. S. Kim, Mater. Lett., 56, 379 (2002)   DOI   ScienceOn
12 L. M. Levinson and H. R. Philipp, Amer. Ceram. Soc. Bull., 65, 639 (1986)
13 C. W. Nahm and C. H. Park, J. Mater. Sci., 35, 3037 (2000)   DOI   ScienceOn
14 C. W. Nahm, J. Eur. Ceram. Soc., 21, 445, (2001)   DOI   ScienceOn
15 D. R. Clarke, J. Amer. ceram. Soc., 82, 485, (1999)