In discrete dislocation plasticity simulations material deformation is evaluated at the microscopic lengthscale by following the motion of individual discrete dislocations. Closed form analytiical formulae for stress fields caused by dislocations can be used to calculate all the force experienced by each dislcoation segment as a result of interactions with all other segments. A velocity law is then used to evaluate new dislocation positions after a small time step. This allows many fundamental deformation processes to be captured in huge detail.
This an exciting development that allows direct comparison with micromechanical testing experiments. However, it is important to properly match the boundary conditions found in the experiments and we have been developing methods to take the simulations to the more realistic finite domain. This requires embedding the discrete dislocation dynamics simulations of plasticity within a finite element analysis framework that handles complex displacement and traction boundary conditions.
Two dimensional problem has been completed and development is now focussed on three dimensions, in parallelisation, and implementation on GPUs. The analysis is generating great insights from micro-mechanical testing projects.
