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arXiv · 1503.02922

Direct observation of size scaling and elastic interaction between nano-scale defects in collision cascades

X. Yi·A. E. Sand·D. R. Mason·M. A. Kirk·S. G. Roberts·K. Nordlund·S. L. Dudarev
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Abstract

Using in-situ transmission electron microscopy, we have directly observed nano-scale defects formed in ultra-high purity tungsten by low-dose high energy self-ion irradiation at 30K. At cryogenic temperature lattice defects have reduced mobility, so these microscope observations offer a window on the initial, primary damage caused by individual collision cascade events. Electron microscope images provide direct evidence for a power-law size distribution of nano-scale defects formed in high-energy cascades, with an upper size limit independent of the incident ion energy, as predicted by Sand et al. [Eur. Phys. Lett., 103:46003, (2013)]. Furthermore, the analysis of pair distribution functions of defects observed in the micrographs shows significant intra-cascade spatial correlations consistent with strong elastic interaction between the defects.

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X. Yi, A. E. Sand, D. R. Mason, M. A. Kirk, S. G. Roberts, K. Nordlund, S. L. Dudarev. 2015-03-10. Direct observation of size scaling and elastic interaction between nano-scale defects in collision cascades. https://doi.org/10.1209/0295-5075/110/36001

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