Details

Autor(en) / Beteiligte

• Mason, D.R.
• Sand, A.E.
• Yi, X.
• Dudarev, S.L.

Titel

Direct observation of the spatial distribution of primary cascade damage in tungsten

Ist Teil von

• Acta materialia, 2018-02, Vol.144 (C), p.905-917

Ort / Verlag

United States: Elsevier Ltd

Erscheinungsjahr

2018

Quelle

Elsevier ScienceDirect Journals

Beschreibungen/Notizen

• Recently we have presented direct experimental evidence for large defect clusters being formed in primary damage cascades in self-ion irradiated tungsten [Yi et al., EPL 110:36001 (2015)]. This large size is significant, as it implies that strong elastic interaction between the defects will affect their subsequent evolution, especially if defects are formed close together. Here we present a direct experimental observation of the separation between visible defects in self-ion irradiated tungsten, in the form of a 2d pairwise radial distribution function extracted from transmission electron micrographs (TEM). We also present a detailed analysis of the observed radial distribution function, and infer the probable size and shape of individual cascades. We propose and validate a simple exponential form for the spatial distribution of defects within a single cascade. The cascade statistics necessary have been acquired by developing an automated procedure for analysing black-dot damage in TEM micrographs. We confirm that the same model also produces a high-quality fit to the separation between larger defects observed in MD simulations. For the first time we present experimental evidence for the sub-nanometre-scale spatial distribution of defect clusters within individual cascades. [Display omitted]