PNNL

Abstract

The interstitial clusters produced by cascades in metals have very high mobility and exhibit thermally activated, one-dimensional glide along the crowdion direction, as revealed by molecular dynamics (MD) simulations. Only small interstitial clusters ( directions, as seen in MD simulations. Small clusters change their direction by a fragment mechanism involving rotation of each crowdion into and out of the dumbbell configuration, whereas the directional change for larger clusters is a two-step process consisting of translation along a direction and rotation into an equivalent direction. The mechanism of changing direction for a tri-interstitial cluster is also investigated using MD simulations.