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Electron Microscopy Studies of Potassium Sodium Niobate Ceramics

Published online by Cambridge University Press:  15 November 2005

Darja Jenko ,
Andreja Benčan ,
Barbara Malič ,
Janez Holc  and
Marija Kosec
Darja Jenko
Affiliation:
“Jožef Stefan” Institute, Electronic Ceramics Department, Jamova 39, SI-1000 Ljubljana, Slovenia
Andreja Benčan
Affiliation:
“Jožef Stefan” Institute, Electronic Ceramics Department, Jamova 39, SI-1000 Ljubljana, Slovenia
Barbara Malič
Affiliation:
“Jožef Stefan” Institute, Electronic Ceramics Department, Jamova 39, SI-1000 Ljubljana, Slovenia
Janez Holc
Affiliation:
“Jožef Stefan” Institute, Electronic Ceramics Department, Jamova 39, SI-1000 Ljubljana, Slovenia
Marija Kosec
Affiliation:
“Jožef Stefan” Institute, Electronic Ceramics Department, Jamova 39, SI-1000 Ljubljana, Slovenia
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Abstract

Using electron microscopy, K0.5Na0.5NbO3 (KNN) ceramics sintered at 1030°C for 8 h and 1100°C for 2 and 24 h was studied. The scanning electron microscopy and X-ray spectrometry revealed that the materials consisted of a matrix phase in which the (Na+K)/Nb ratio corresponded closely to the nominal composition and a small amount of Nb-rich secondary phase. A bimodal microstructure of cube-shaped grains was revealed in the fracture and thermally-etched surfaces of the KNN. In the ceramics sintered at 1100°C, the larger grains (up to 30 μm across), contained angular trapped pores. The transmission electron microscopy analysis revealed that the crystal planes of the grains bordering the intragranular pore faces were of the {100} family with respect to the simple perovskite cell. Ferroelectric domains were observed in the grains of this material.

Keywords

potassium sodium niobatesynthesissinteringscanning electron microscopytransmission electron microscopycube-shaped grainsangular poresferroelectric domains
Type
Papers from the European Microbeam Analysis Society Regional Workshop in Bled, Slovenia
Information
Microscopy and Microanalysis , Volume 11 , Issue 6 , December 2005 , pp. 572 - 580
Copyright
© 2005 Microscopy Society of America

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References

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