The fundamentals of plastic deformation : several case studies of plasticity in confined volumes.

Plasticity in small volumes is significantly different than in large, bulk-like specimens. The strength of materials in the micron and sub-micron regime depends not only on the microstructure but also on the size of the material. Given that a number of important mechanical processes occur at these length scales, it is important to build a comprehensive understanding of these materials and processes. This work examines several different processes in small volumes. The motion of dislocations in the drag regime are examined as a function of material volume which exhibits higher drag than in the bulk. The stability of single arm sources are also investigated using molecular dynamics. Finally, dislocation nucleation from the free surface is investigated using both atomistic as well as continuum models. These results provide a better understanding of plastic processes in confined volumes.