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Microstructure reconstructions resulting from diffraction contrast tomography data of polycrystalline bulk strontium titanate were reinvestigated by means of electron backscatter diffraction (EBSD) characterization. Corresponding two-dimensional grain maps from the two characterization methods were aligned and compared, focusing on the spatial resolution at the internal interfaces. The compared grain boundary networks show a remarkably good agreement both morphologically and in crystallographic orientation. Deviations are critically assessed and discussed in the context of diffraction data reconstruction and EBSD data collection techniques. [ABSTRACT FROM AUTHOR]

Motivated by the recently reported a growth anomaly in strontium titatate bulk samples1, 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 model3. [ABSTRACT FROM AUTHOR]

Depending on the process parameters, the directional solidification (DS) of eutectic alloys leads to a fibrous or lamellar microstructure. A physically motivated creep model which was evaluated for a DS-eutectic with a fibrous microstructure is applied to a DS-eutectic with a lamellar microstructure. Creep curves are simulated and compared to experimentally measured ones. It is shown, that the simulation is in good agreement with the experiment. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]

A small-deformation strain gradient plasticity (GP) model for single-crystals has been proposed in [1], including a grain boundary (GB) yield condition without hardening. It has been extended by a hardening term for the GBs after a comparison to discrete dislocation dynamics (DDD) results in [2]. Differences between the strain gradients of the GP results and the DDD results motivate the consideration of a non-quadratic defect energy [3] in the GP model. It is shown that the gradients in the GP model can be improved using an exponent different from two. Remaining discrepancies in the strain profiles, compared to the DDD results, are attributed to the neglect of the individual gradients of plastic slip and due to the lack of a mechanism for the misorientation-dependent elastic interactions of dislocations across GBs [4] in the GP model. (© 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim) [ABSTRACT FROM AUTHOR]