[2H05-08] Irradiation Effect 1

[2H08] Inhomogeneous Distribution of Ni and Si atoms in Solute Clusters in Irradiated Stainless Steels

*Dongyue Chen¹, Kenta Murakami², Kenji Dohi³, Kenji Nishida³, Liang Chen¹, Naoto Sekimura¹ (1. The University of Tokyo, 2. Nagaoka University of Technology, 3. Central Research Institute of Electric Power Industry)

Keywords:Stainless steel, Ni-Si clusters, Atom probe tomography

Dislocation loops may act as nucleation sites for the Ni-Si solute clusters in stainless steels. However, direct proofs cannot be provided because loops cannot be identified by atom probe tomography (APT). If the inhomogeneous distribution of solutes in solute clusters can be quantitatively analyzed, the role of loops in precipitation may be clarified. It is difficult to extract the information of solute distribution in clusters from atom maps, because the shape, size and definition of clusters need to be considered. In this work, attempts were made to develop methods for solute distribution analysis in clusters; irradiated stainless steel with large size of Ni-Si clusters were taken as an example to assess the method. The results are compared with the loop size and orientation results by transmission electron microscopy (TEM).