  Mechanical properties of porous SOFC electrodes are largely determined by
their microstructures. Measurements of the elastic properties and
microstructural parameters can be achieved by modelling of the digitally
reconstructed 3D volumes based on the real electrode microstructures. However,
the reliability of such measurements is greatly dependent on the processing of
raw images acquired for reconstruction. In this work, the actual
microstructures of La0.6Sr0.4Co0.2Fe0.8O3-d (LSCF) cathodes sintered at an
elevated temperature were reconstructed based on dual-beam FIB/SEM tomography.
Key microstructural and elastic parameters were estimated and correlated.
Analyses of their sensitivity to the grayscale threshold value applied in the
image segmentation were performed. The important microstructural parameters
included porosity, tortuosity, specific surface area, particle and pore size
distributions, and inter-particle neck size distribution, which may have
varying extent of effect on the elastic properties simulated from the
microstructures using FEM. Results showed that different threshold value range
would result in different degree of sensitivity for a specific parameter. The
estimated porosity and tortuosity were more sensitive than surface area to
volume ratio. Pore and neck size were found to be less sensitive than particle
size. Results also showed that the modulus was essentially sensitive to the
porosity which was largely controlled by the threshold value.
