Since the mid 80s various gradient plasticity models have been developed for obtaining the plastic response of materials at the micron- and submicron- scales. In particular, gradient terms have been proven to be crucial for understanding size effects in constrained plastic flow, which are related to the emergence of plasticity boundary layers near passive (plastically not deformable) boundaries. In spite of the success of gradient theories in modeling boundary layer formation, there remain unresolved issues concerning the physical interpretation of the internal length scale involved in the theoretical formulation. Physically, boundary layer formation is related to the piling up of dislocations against the boundaries. This phenomenon is investigated by performing discrete dislocation dynamics (DDD) simulations on a tri-crystal with plastically non-deforming grain boundaries. Strain distributions are derived from the DDD simulations and matched with the results of gradient plasticity calculations, in order to identify the internal length scale governing the boundary layer width.
|Original language||English (US)|
|Journal||IOP Conference Series: Materials Science and Engineering|
|State||Published - 2009|
|Event||3rd International Conference on the Fundamentals of Plastic Deformation, DISLOCATIONS 2008 - Hong Kong, Hong Kong|
Duration: Oct 13 2008 → Oct 17 2008
ASJC Scopus subject areas
- Materials Science(all)