The quasi-continuum method was used to simulate 3-dimensional Lomer-Cottrell junctions in the absence or presence of an applied stress. The results showed that this type of junction was destroyed by an unzipping mechanism in which the dislocations that formed the junction were gradually pulled apart along the junction segment. The calculated critical stress which was needed in order to break the junction was comparable to that predicted by line-tension models. The simulations also revealed a marked effect of the initial dislocation line directions upon the breaking mechanism. This effect was neglected by macroscopic treatments of hardening by junctions.

Structure and Strength of Dislocation Junctions: an Atomic Level Analysis. D.Rodney, R.Phillips: Physical Review Letters, 1999, 82[8], 1704-7