Behaviour of helium in UO2 single crystals: a transmission electron microscopy investigation |
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Authors: | K. Hiraga T. Ohsuna S. Nishimura |
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Affiliation: | Centre de Spectrométrie Nucléaire et de Spectrométrie de Masse , Institut de Physíque Nucléaire et de Physíque des Particules, CNRS, Université Paris Sud , batiment 104-108, F-91405 Orsay Campus, France |
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Abstract: | We have found that the structure of an Al-Ni-Co decagonal quasicrystal, which shows a diffraction pattern with many superlattice reflections (called a 'type I superlattice'), can be described as an ordered arrangement of two kinds of atomic columnar cluster with different orientations of their pentagonal symmetry. The fundamental lattice, which is constructed by connecting the clusters, is a rhombic quasiperiodic lattice with a bond length of about 2nm. The two kinds of cluster are placed at the lattice points in a definite manner such that the two connected clusters have different orientations. |
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Keywords: | Steel embrittlement ultrafine microstructure toughness grain boundary segregation delamination fracture |
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