COMBINING X-RAY DIFFRACTION CONTRAST TOMOGRAPHY AND MESOSCALE GRAIN GROWTH SIMULATIONS IN STRONTIUM TITANATE: AN INTEGRATED APPROACH FOR THE INVESTIGATION OF MICROSTRUCTURE EVOLUTION

摘要

Motivated by the recently reported a growth anomaly in strontium titatate bulk samples', the microstructure of bulk strontium titanate has been investigated by an integrated approach comprising conventional metallography, three dimensional X-ray diffraction contrast tomography (DCT)2, and the observation of pore shapes in combination with mesoscale grain growth simulations. The microstructural evolution in strontium titanate has been characterized alternating ex-situ annealing and high energy X-ray DCT measurements, resulting in three dimensional microstructure reconstructions which are complemented by crystallographic orientations obtained from diffraction information. These investigations allow to establish a correlation between grain morphology, orientation dependent grain boundary properties and growth behavior in these highly anisotropic materials. Together with energy and mobility data gathered in conventional metallographical analysis, they serve as input for a 3D vertex dynamics model~3.