Small-scale characterisation of irradiated nuclear materials: Part I – Microstructure

Abstract

Article history:Available online xxxx a b s t r a c tThe behaviour of nanometre-scale precipitates in oxide dispersion strengthened (ODS) ferritic alloys and tungsten-rhenium alloys for nuclear applications has been examined by atom probe tomography (APT). Low Re content tungsten alloys showed no evidence of Re clustering following self-ion irradiation whereas the 25 at.% Re resulted in cluster formation. The size and composition of clusters varied depending on the material form during irradiation (pre-sharpened needle or bulk). These results highlight the care that must be taken in interpreting data from ion irradiated pre-sharpened needles due to the presence of free surfaces. Self-ion irradiation of the ODS ferritic alloy resulted in a change in the composition of the clusters, indicating a transition from a near-stoichiometric Y 2 Ti 2 O 7 composition towards a Ti 2 YO 5 .Published by Elsevier B.V. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/3.0/).

Irradiation damage concurrent challenges with RAFM and ODS steels for fusion reactor first-wall/blanket: a review

“…Extensive ion irradiation literature exists on a wide range of ODS steels where nano-dispersoids are reported to be stable over the irradiation temperature and dose ranges of RT-835 • C and ion doses from ∼2 to 200 dpa [205, 233, 234, 237, 240, 243, 247-249, 251, 259, 263]. However, substantial literature also exists over a similar ion irradiation temperature and dose range, where deterioration of the oxide particles is reported [205,219,222,226,231,235,238,239,241,242,245,250,257,261,262,264,265]. The majority of these reports typically show changes in the size or number density of the nano-dispersoids, while irradiations in the temperature range of RT-400 • C have also shown radiation-induced amorphisation (RIA) of the oxide particles in many ODS steels [196,229,235,243,251,261,264].…”

Perspectives on multiscale modelling and experiments to accelerate materials development for fusion

“…X-ray techniques available at advanced synchrotron light sources offer ultra-high brightness relative to standard laboratory sources, and in turn provide rapid measurements facilitating both high-throughput and in situ experiments [298][299][300] . When leveraged in a multi-modal fashion with conventional characterization methods (e.g., TEM [132,146,167,199,[301][302][303] , PAS [304,305] , APT [185,186,188,194,203,213,306,307] , and SANS [ 186,192,204,308 ]), these techniques provide a fundamental understanding of key parameters that lead to microstructural changes and thermomechanical performance degradation. Such ap- proaches also facilitate direct validation of mechanistic models for material performance through unprecedented access to realistic morphology and microstructural information [310][311][312] .…”

Design and Demonstration of a Material-Plasma Exposure Target Station for Neutron Irradiated Samples

“…25 and 26 also discuss several values of E d for tungsten. For the irradiation of tungsten samples in the high fast-flux environment in the HFIR flux trap region, the rate at which displacement damage accumulates was determined to be 1.0±7% DPA per HFIR cycle, when an effective E d of 42 eV 26,27,28 is considered. For the simulated irradiations discussed in this paper, it was assumed the samples are irradiated in HFIR for 10 cycles, giving an expected displacement damage level of 10 DPA for the irradiated tungsten.…”