Molecular dynamics simulations showed that, in an embedded-atom method crystal, interstitial loops with appropriate geometries and made of four <110> dumb-bells were absorbed by the Shockley partials of both static and gliding edge dislocations. Depending upon the applied stress the loops could be either dragged and undergo atomic-level rearrangements, or could un-pin from the dislocation. Such loops introduced an additional friction, during dislocation glide, whose magnitude was deduced from the simulations. Similar effects were also observed when loops with different geometries stabilized a few lattice planes away from the dislocation glide plane.

Dislocation Pinning by Small Interstitial Loops: a Molecular Dynamics Study. D.Rodney, G.Martin: Physical Review Letters, 1999, 82[16], 3272-5