Associate Professor Marek Faryna
Correlation between ceramics microstructure and functional properties.
Microstructure of ceramic materials may be better understood by establishing of crystallographic relationships between several adjacent grains. Such measurements can be performed in the transmission electron microscope (TEM) by studying crystallographic relationships neighboring grains in the selected area electron diffraction (SAED) mode. However, the TEM limits the observation area to a few grains only which makes gathering reasonable statistical data fairly difficult. To overcome this problem, Electron BackScatter Diffraction (EBSD) in the Scanning Electron Microscope (SEM) has been successfully applied. It provides information about the orientation of crystals with a spatial resolution in the range of few tens of nanometers depending on acceleration voltage of electron beam and the density of specimen. By applying of EBSD a relatively large number of diffraction patterns from several hundreds crystallites can be collected, indexed and stored during a single experiment. Consequently, orientation relationships between many grains can be established in a much bigger composite volume.
Microstructure and its influence on functional properties of four selected groups of ceramic materials will be discussed:
a) TZP-based composites,
b) Alumina-base composites,
b) Hydroxyapatite (Hap) and related bioceramic materials,
c) Piezoelectric ceramics (PLZT).
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