Quantification of micrometre-sized porosity in quasicrystals using coherent synchrotron radiation imaging.

Phase contrast radiography has been applied to investigate porosity in the bulk of quasicrystals. The pores act on X-rays as lenses, leading to drastic changes in the phase contrast images of pores. Depending on the recording conditions and pore features, different imaging regimes are accessed. The variation of the contrast makes the direct characterization of pores from image data, in terms of a precise determination of their size and volume, unreliable. The contrast in Fresnel diffraction images of pores was thus investigated with the support of numerical simulations. A phase retrieval procedure was carried out in order to obtain the correct information from the pore images.