The glide of dislocation pairs (super-dislocations) in an order-strengthened single crystal was simulated, and the critical resolved shear stress was derived. The simulations were based upon the local stress equilibrium in one glide plane. Elastic interaction of the dislocations with one another, and with themselves, was allowed for. The mean particle radius, the volume fraction and the energy of the antiphase boundary created by the leading dislocation of a pair were varied. In particular, the transition from the peak-aged to the overaged aging state was covered by these parameters. In the peak-aged state, the dislocations glided in pairs. Upon approaching the overaged state, they became decoupled by Orowan loops left behind by the leading dislocation.

The Critical Resolved Shear Stress of Single Crystals with Long-Range Ordered Precipitates Calculated by Dislocation Dynamics Simulations. V.Mohles: Materials Science and Engineering A, 2004, 365[1-2], 144-50