Published 1989 | Version v1
Miscellaneous Metadata-only

Study of the ceramic phases in ZnO varistors

Creators

  • 1. Sao Carlos Univ., SP (Brazil). Dept. de Materiais
  • 2. Sao Carlos Univ., SP (Brazil). Dept. de Quimica
  • 3. UNESP, Araraquara, SP (Brazil)
  • 4. Instituto Militar de Engenharia, Rio de Janeiro, RJ (Brazil)

Description

The electrical properties of ZnO varistors are highly dependent on the ceramic phases that constitute it. With the purpose of understanding the evolution of the ceramic phases in ZnO varistors, several ceramic systems have been systematically studied. The samples have been characterized by X-ray diffraction, scanning electron microscopy and EPR. From this analysis, three ceramic phases have been identified: one phase of ZnO dissolving CoO, MnO and Cr2O3, a second spinel phase also dissolving CoO, MnO2 and Cr2O3, but in higher proportions, and a third phase rich in bismuth, such as β-Bi2O3. (author)

Availability note (English)

Available from the Library of the Comissao Nacional de Energia Nuclear, RJ, Brazil.

Abstract (Portuguese)

As propriedades eletricas dos varistores de oxido de zinco sao profundamente dependentes das fases ceramicas constituintes. Com o objetivo de se entender a evolucao das fases ceramicas em varistores de ZnO, estudou-se sistematicamente varios sistemas ceramicos. As amostras foram caracterizadas por difracao de raios-X, microscopia de varredura e EPR. Desta analise tres fases ceramicas foram identificadas: uma fase ZnO dissolvendo CoO, MnO2 e Cr2O3, uma fase espinelio tambem dissolvendo CoO, MnO2 e Cr2O3, porem em maiores quantidades, e uma terceira fase rica em bismuto to tipo β-Bi2O3. (author)

Additional details

Additional titles

Original title (Portuguese)
Estudo das fases ceramicas em varistores de ZnO

Publishing Information

Imprint Title
Proceedings of the 33. Brazilian Congress of Ceramic. V. 1
Imprint Pagination
505 p.
Journal Page Range
p. 101-115.

Conference

Title
33. Brazilian Congress of Ceramic.
Dates
28-31 May 1989.
Place
Serra Negra, SP (Brazil).

INIS

Country of Publication
Brazil
Country of Input or Organization
Brazil
INIS RN
20083784
Subject category
S36: MATERIALS SCIENCE;
Resource subtype / Literary indicator
Conference, Non-conventional Literature
Descriptors DEI
ELECTRON SPIN RESONANCE; PHASE STUDIES; SCANNING ELECTRON MICROSCOPY; SEMICONDUCTOR RESISTORS; X-RAY DIFFRACTION; ZINC OXIDES
Descriptors DEC
CHALCOGENIDES; COHERENT SCATTERING; DIFFRACTION; ELECTRICAL EQUIPMENT; ELECTRON MICROSCOPY; EQUIPMENT; MAGNETIC RESONANCE; MICROSCOPY; OXIDES; OXYGEN COMPOUNDS; RESISTORS; RESONANCE; SCATTERING; SEMICONDUCTOR DEVICES; ZINC COMPOUNDS

Optional Information

Notes
Imprint:Anais do 33. Congresso Brasileiro de Ceramica. V. 1.