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http://dx.doi.org/10.4313/JKEM.2004.17.11.1186

Electrical Properties of ZnO Varistors with Variation of Co3O4  

Cho, Hyun-Moo (서남대학교 전기전자공학부)
Lee, Sung-Gap (서남대학교 전기전자공학부)
Publication Information
Journal of the Korean Institute of Electrical and Electronic Material Engineers / v.17, no.11, 2004 , pp. 1186-1191 More about this Journal
Abstract
ZnO varistor ceramics which were fabricated with variation of added of 0.5～1.0 mol% Co$_3$O$_4$, were sintered at 1150 $^{\circ}C$. In the specimen added 0.7 mol% Co$_3$O$_4$, sintered density was 6.03 g/㎤ and electrical properties were superior to any other compositions. The nonlinear coefficient a and clamping voltage ratio were 83 and 1.35, respectively. But, endurance surge current in the specimen added 0.5 mol% Co$_3$O$_4$ was 7000 A/$\textrm{cm}^2$, and deviation of varistor voltage was Δ-3.23 %. As P.C.T and T.C.T environmental test were succeed in all specimens, and deviation of varistor voltage in the specimen added 0.6 mol% Co$_3$O$_4$ was Δ-0.81 %. All specimens showed good leakage current property on the High Temperature Continuous Load Test(HTCLT) for 1000 hr at 85 $^{\circ}C$ and variation rate of the varistor voltage below Δ-2.0 %.
Keywords
$Co_{3}O_{4}$; Nonlinear coefficient; P. C. T; T. C. T; Endurance surge current; High temperature continuous load test;
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  • Reference
1 J. J. Lee, K. O'brien, and M. S. Cooper, 'Second-breakdown characteristics of metal-oxide varistors', J. Appl. Phys., Vol. 48, No. 3, p. 1252, 1977   DOI   ScienceOn
2 K. Sato, Y. Takada, H. Maekawa, M. Otokake, and S. Tominaga, 'Electrical conduction of ZnO varistors under continuous dc stress', Jpn. J. Appl. Phys., Vol. 19, Co. 5, p. 909, 1980   DOI
3 電氣學會, '酸化亞鉛避器の特性と試驗評價法', 電氣學會技術報告, 474号, 1993
4 K. Mukae, K. Tsuda, and I. Nagasawa. 'Non-ohmic properties of ZnO-rare earth metal oxide-&Co_3O_4& ceramics', Jpn. J. Appl. Phys., Vol. 16, No. 8, p. 1361, 1977   DOI
5 남춘우, 류정선, 'ZPCCE계 바리스터의 미세구조와 전기적 성질 및 안정성', 전기전자재료학회논문지, 13권, 9호, p. 735, 2001
6 한세원, 조한구, 강형부, 'ZnO 바리스터에서 첨가물이 쌍정에 미치는 영향', 전기전자재료학회 하계학술대회 논문집, p. 1057, 2001
7 M. Matsuoka, 'Nonohmic properties of zinc oxide ceramics', Jpn. J. Appl. Phys., Vol. 10, No. 6, p. 736, 1971   DOI
8 IEC 60068, Part. No. 2, 'Environmental Test', 1982
9 C. W. Nham, 'ZnO-$Pr_6O_11$-CoO-$Cr_2O_3$-$Er_2O_3$ based-ceramic varistors with high stability of nonlinear properties', J. Mater. Sci. Lett., Vol. 21, No. 3, p. 201, 2002   DOI   ScienceOn
10 남춘우, 박종아, 김명준, 유대훈, '소결온도에 따른 ZPCCE계 바리스터의 제한전압특성', 전기전자재료학회논문지, 17권, 8호, p.835, 2004
11 IEC 61000-4-5 Standard 1.2/50 ${\mu}s$ - 8/20 ${\mu}s$ voltage-current combination pulse
12 IEC 60060 High-voltage test techniques - Measuring systems
13 IEC 1000-4-series, Electromagnetic Compatibility