Analysis of secondary phases segregated and precipitated in SnO2-based varistors

Transmission and scanning electron microscopy techniques were used to study the heterogeneities found in the microstructure of SnO2·Co3O4· Nb2O5·Fe2O3 and SnO2·ZnO·Nb2O5·Fe2O3 varistors. Second phases encountered both inside the grains and in grain boundary regions were identified using energy dispe...

ver descrição completa

Detalhes bibliográficos
Autores: Parra, Rodrigo, Castro, Miriam Susana, Varela, J. A.
Formato: artículo
Estado:Versión publicada
Fecha de publicación:2004
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/27976
Acesso em linha:http://hdl.handle.net/11336/27976
Access Level:acceso abierto
Palavra-chave:Electron Microscopy
Grain Boundaries
Microstructure-Final
Varistors
https://purl.org/becyt/ford/2.5
https://purl.org/becyt/ford/2
https://purl.org/becyt/ford/1.4
https://purl.org/becyt/ford/1
Descrição
Resumo:Transmission and scanning electron microscopy techniques were used to study the heterogeneities found in the microstructure of SnO2·Co3O4· Nb2O5·Fe2O3 and SnO2·ZnO·Nb2O5·Fe2O3 varistors. Second phases encountered both inside the grains and in grain boundary regions were identified using energy dispersive spectrometry and electron diffraction patterns. Through the electrical characterisation, the presence of iron oxide among the additives was determined to highlight the non-linear properties of the specimens. A discussion on the influence of second phases on the non-linear features of these systems is also addressed.