Frau Špringer Šimonová ist assoziiertes Mitglied des Graduiertenkollegs GRK 2802. Sie wurde am Institut für Glas und Keramik der Universität für Chemie und Technologie (VŠCHT)  in Prag von Prof. Dr. Dipl.-Min. Willi Pabst betreut. Ihre Dissertation beschäftigt sich mit der Entwicklung und Charakterisierung von SnO₂-ZnO basierten sowie kaolinbasierten Oxidkeramiken. Beide Arten von oxidischer Keramik wurden mit Hilfe konventioneller Sinterung hergestellt, wobei ihre Mikrostruktur, ihre Phasenzusammensetzung sowie ihre elastischen Eigenschaften charakterisiert wurden. Zusätzlich wurden SnO₂-ZnO basierten Keramik mit Hilfe von Mikrowellen gesintert und mit der konventioneller Sinterung verglichen.

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Kurzfassung der Dissertation von Ing. Petra Špringer Šimonová

This dissertation is a collection of nine original research papers and highlights the key findings on the relationships between processing, microstructure, and effective elastic properties of selected oxide and silicate ceramics, with a focus on SnO₂-ZnO based oxide ceramics and kaolin-based ceramics. Both types of ceramics are prepared using conventional sintering, and their microstructure, phase composition, and elastic properties are thoroughly characterized. Additionaly, microwave sintering is applied to SnO₂-ZnO based ceramics to compare its effects with conventional sintering.

The first part of the thesis focuses on SnO₂-ZnO based oxide ceramics. SnO₂ ceramics have emerged as an interesting material to investigate since their behavior differs from that of usual oxide ceramics in terms of microstructure evolution during sintering. There is no change in the overall prorosity, only in the shape and size of pores. Therefore, changes inits effective properties, such as Young´s modulus, have to be attributed to other microstructural parameters. On the other hand, ZnO ceramics do not exhibit such exotic sintering behavior and changes in its effective properites are mainly determined by changes in porosity. Composite SnO₂-ZnO based oxide ceramics contain spinel-type Zn₂SnO₄ as an additional phase, and the evolution of their effective properties is intermediate between SnO₂ and ZnO ceramics.

The second part of the thesis investigate kaolin-based silicate ceramics. In this case, the focus is not only on the evolution of microstructure but also on understanding the relationship between phase composition and elastic properties. A key part of the research involeves determining the phase composition by X-ray diffraction, including the glass phase content, which plays a crucial role in the final elastic properties of these ceramics.

In addition to the experimental investigation, which focuses on the impulse excitation technique, the dissertation provides insight into the prediction of effective properties, particularly elastic properties and the porosity dependence of sound velocities, for which new models have been proposed.