Investigation of structural defects and inhomogeneities in Al-Pd-Mn icosahedral quasicrystals by combined synchrotron X-ray topography and phase radiography

Abstract

Phase-sensitive radiography, made possible by the lateral coherence of the beams from third-generation synchrotron-radiation sources, has been combined with monochromatic X-ray topography in an investigation of structural defects and inhomogeneities in the bulk of Al-Pd-Mn icosahedral single quasicrystal grains. Loop-shaped defects previously observed by X-ray topography are thus related with holes and second phase precipitates revealed by phase radiography. The evolution of these defects after annealing provides clues on their nature and formation.