Varistor Properties and Aging Behavior of V/Mn/Co/ La/Dy Co-doped Zinc Oxide Ceramics Modified with Various Additives
| Autor: | Choon-Woo Nahm |
|---|---|
| Rok vydání: | 2014 |
| Předmět: |
Materials science
Metallurgy Analytical chemistry Varistor chemistry.chemical_element Zinc Microstructure Accelerated aging Grain size Electronic Optical and Magnetic Materials Stress (mechanics) chemistry Phase (matter) visual_art visual_art.visual_art_medium Ceramic Electrical and Electronic Engineering |
| Zdroj: | Transactions on Electrical and Electronic Materials. 15:284-289 |
| ISSN: | 1229-7607 |
| Popis: | The effects of additives (Nb, Bi and Cr) on the microstructure, varistor properties, and aging behavior of V/Mn/Co/ La/Dy co-doped zinc oxide ceramics were systematically investigated. An analysis of the microstructure showed that all of the ceramics that were modified with various additives were composed of zinc oxide grain as the main phase, and secondary phases such as Zn3(VO4)2, ZnV2O4, and DyVO4. The Bi2O3-modified samples exhibited the lowest density, the Nb2O5-modified sample exhibited the largest average grain size, and the Cr 2O3-modified samples exhibited the highest breakdown field. All additives improved the non-ohmic coefficient ( α) by either a small or a large margin, and in particular an Nb2O5 additive noticeably increased the non-ohmic coefficient to be as large as 36. The Bi2O3-modified samples exhibited the highest stability with variation rates for the breakdown field and for the non-ohmic coefficient ( α) of -1.2% and -26.3%, respectively, after application of a DC accelerated aging stress of 0.85 EB/85℃/24 h. |
| Databáze: | OpenAIRE |
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