Dislocation dynamics simulations were made of the glide of dislocations in random populations of Frank loops. Specific local interaction rules were developed in order to reproduce elementary interaction mechanisms deduced from molecular dynamics simulations. It was shown that the absorption of Frank loops, as helical turns on screw dislocations, was the basis of clear band formation. It transformed the loops into jogs on dislocations and, when the dislocations unpinned, the jogs were transported along the dislocation lines; leading to progressive clearing of the band. Finally, the dislocations were re-emitted in a glide plane which was different to the original one; thus permitting a broadening of the band. It was also shown that isolated dislocations could not form a clear band of finite thickness because the clearing process would be limited to one plane that was tilted with respect to the {111} primary plane. Instead, a pile-up of dislocations was required; leading to collective effects between dislocations.

Clear Band Formation Simulated by Dislocation Dynamics  - Role of Helical Turns and Pile-Ups. T.Nogaret, D.Rodney, M.Fivel, C.Robertson: Journal of Nuclear Materials, 2008, 380[1-3], 22-9