Helium behaviour in UO2 through low fluence ion implantation studies
Langue
en
Article de revue
Ce document a été publié dans
Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms. 2014, vol. 327, p. 113-116
Elsevier
Résumé en anglais
In this work we focus on experiments involving implantation of 500 keV 3He ions in sintered polycrystalline material. Samples are implanted at low fluences (∼2 ×1013 ions/cm2) and subsequently isothermally annealed in a ...Lire la suite >
In this work we focus on experiments involving implantation of 500 keV 3He ions in sintered polycrystalline material. Samples are implanted at low fluences (∼2 ×1013 ions/cm2) and subsequently isothermally annealed in a highly sensitive thermal desorption spectrometry (TDS) device PIAGARA (Plateforme Interdisciplinaire pour l'Analyse des GAz Rares en Aquitaine). The helium fluencies studied are two to three orders of magnitude lower than previous Nuclear Reaction Analysis (NRA) experiments carried out on identical samples implanted at identical energies. The fractional release of helium obtained in the TDS experiments is interpreted using a three-dimensional axisymmetric diffusion model which enables results to be quantitatively compared to previous NRA data. The analysis shows that helium behaviour is qualitatively independent of ion fluency over three orders of magnitude: helium diffusion appears to be strongly inhibited below 1273 K within the centre of the grains presumably as a result of helium bubble precipitation. The scenario involving diffusion at grain boundaries and in regions adjacent to them observed at higher fluencies is quantitatively confirmed at much lower doses. The main difference lies in the average width of the region in which uninhibited diffusion occurs.< Réduire
Mots clés en anglais
Helium
Uranium dioxide
Thermal desorption spectroscopy
Origine
Importé de halUnités de recherche