Processing of lead-based antiferroelectric Ceramics
Mirjam Skof, Theresa Kainz, Klaus Reichmann
Institut für Chemische Technologie von Materialien, TU Graz
15:20 - 17:30 Thursday 24 October 2013 Foyer Alte Technik For lead-based ceramics, the sinterability and densification of the samples strongly depends on the sinter temperatures used. With PbO as the volatile compound the experimental set-up as well as the maintaining of the atmosphere during sintering is crucial. An aggressive depletion of PbO leads to the formation of secondary phases and low densities.
Two basic compositions of PLZT were prepared according to the following formula (Pb0,89AE0,02La0,06)(Zr1-xTix)O3 (AE = Ca, Sr, Ba; x = 0,10 & 0,15), processed via the mixed oxide route, calcined at 925°C and sintered at 1250°C. An excess of 2 % PbO was added prior calcination.
To control the sintering, the samples were analyzed in terms of their densities, mass loss and shrinkage. XRD analyses were carried out to control the formation of the perovskite structure; the proper sintering temperature was determined by Dilatometry. The microstructure was analyzed via SEM in channeling contrast mode.
The dielectric properties were measured by determining the permittivity ε, the loss factor and the piezoelectric constant d33. Furthermore polarization curves were recorded leading to the switching field.
|
