[KSCI] Korea Science Citation Index Service

http://dx.doi.org/10.4313/TEEM.2005.6.4.144

Influence of Dysprosia Addition on Microstructure and Electrical Properties of Praseodymia-based Zinc Oxide Varistors

Nahm, Choon-Woo (Department of Electrical Engineering, Dongeui University)

Publication Information

Transactions on Electrical and Electronic Materials / v.6, no.4, 2005 , pp. 144-148 More about this Journal

Abstract

The microstructure and electrical properties of varistor ceramics, which are composed of Zn-PrCo-Cr-Dy-oxide system, were investigated at various dysprosia $(Dy_2O_3)$ addition contents. The $DY_2O_3$ microstructurally played the role of inhibition for the densification and grain growth. As the $DY_2O_3$ content increased, the density decreased in the range of $5.51-4.90 g/cm^3$ , reaching maximum at $0.5 mol\%$ and the average ZnO grain size decreased in the range of $17.7-6.0{\mu}m$ . The incorporation of $DY_2O_3$ significantly improved the nonlinear properties of varistors, above 30 in nonlinear exponent, compared with that without $DY_2O_3$ . The varistors with the best performance of nonlinear properties was obtained $DY_2O_3$ content of $1.0 mol\%$ , 49 in nonlinear exponent and $0.5{\mu}A$ in leakage current.

Keywords

Microstructure; Electrical properties; Varistors;

Citations & Related Records

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