Stability of nanoclusters in 14YWT oxide dispersion strengthened steel under heavy ion-irradiation by atom probe tomography

The Mechanism of Radiation-Induced Nanocluster Evolution in Oxide Dispersion Strengthened and Ferritic-Martensitic Alloys

“…In the initial reconstruction using ICF = 1.65 ( Figure 7.9a), clusters appear to be more horizontally elongated, particularly towards the outer extremes of the represented volume. This result is inconsistent with the observation of TEM-resolution nanoclusters [8] and in the archival literature [12,84,96,110], in which oxide nanoclusters tend to take a spherical shape. On the other hand, clusters in this latter iteration ( Figure 7.9b) appear to be more consistently spherical in shape.…”

“…Similarly, the data in literature also presents contradictory results with respect to irradiation temperature. Ti ratio has been observed to both increase in some studies [8,9,59,67,88,104,114,116], and decrease in others [81,89,102,116,123,124], while the (T+Ti):O ratio is typically observed to remain the same [8,9,116]. A summary of literature data providing evolution information for these two ratios is provided in Figure 2 Cr enrichment at the interface of nanoclusters [107,112], or depletion of Al from nanoclusters [88,104].…”

“…Since other authors have observed composition changes of nanoclusters under irradiation [8,9,13,59,104,124,174], it is considered likely that the dmax and Nmin values may also differ for each specimen. As a result, both parameters are determined independently for each specimen and each individual data set.…”

“…Some authors have suggested methods to remove Fe from the nanoparticle composition [176], while others publish the composition data as-measured [8,9], or publish both the "uncorrected" and "matrix corrected"…”

“…The combined effective ICF selection and normalization step thus enables a more reliable measurement of the oxide nanocluster irradiation evolution. [6,8,9,24,25,40,59,86]. Local electrode atom probe (LEAP) tomographic cluster analysis algorithms provide an objective means to identify and measure the size and number density of these nanoscale phases [167].…”