Dislocation dynamics simulations were used to study the stress-strain response of single-crystal micropillars containing initial dislocation networks generated via a relaxation procedure intended to approximate real thermal annealing processes. It was found that, when such networks were loaded, they exhibited periods of plastic deformation, caused by the operation of single junction-stabilized spiral sources, followed by intervals of purely elastic straining when the sources shut down. The results provided an insight into the mechanisms responsible for the experimentally observed staircase stress-strain behaviour.

Dislocation-Source Shutdown and the Plastic Behaviour of Single-Crystal Micropillars. H.Tang, K.W.Schwarz, H.D.Espinosa: Physical Review Letters, 2008 100[18], 185503