A study of nano-indentation using coupled atomistic and discrete dislocation (CADD) modeling

The phenomenon of nano-indentation into a thin film bonded to a rigid substrate is simulated using a recently developed technique whereby a fully atomistic region is coupled to a continuum region. There are three unique features of the model, as compared to several other coupled techniques that are available. First, the continuum region may contain any number of discrete dislocations, modeled as elastic defects. Second, these dislocations are mechanically coupled to one another and to the atomistic region, thus providing the atomistic region with the appropriate stress environment due to the longrange interaction with the dislocations. Finally, the method includes algorithms for automatically detecting and passing dislocations between the atomistic and continuum regions, taking care of the kinematics of slip at the atomistic/continuum interface