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Sol-gel processing of varistor powders

Published online by Cambridge University Press:  31 January 2011

Gert Hohenberger
Affiliation:
Universität Erlangen/Nürnberg, Institut für Werkstoffwissenschaften III, Martensstr. 5, D-8520 Erlangen, Germany
Gerhard Tomandl
Affiliation:
Universität Erlangen/Nürnberg, Institut für Werkstoffwissenschaften III, Martensstr. 5, D-8520 Erlangen, Germany
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Abstract

A new sol-gel method for the preparation of ZnO varistor powders, using inexpensive source materials such as acetates and nitrates, is described. It yields powders with a more homogeneous distribution of dopants compared to the commercially used mixed oxide technique. Varistor ceramics made from sol-gel powders can be sintered at lower temperatures and show improved electrical behavior. This is a consequence of formation of more varistor-active grain boundaries within the ceramics.

Type
Communications
Copyright
Copyright © Materials Research Society 1992

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