Mesoscale investigations for the evolution of interfaces in plasticity

The ultra-high density of bimetal interfaces in nanolayered metal composites is responsible for exceptional five- to ten-fold increases in strength over that of the constituent phases. How interfaces cause such outstanding results is not fully understood. On the one hand, interfaces fundamentally alter the physical mechanisms responsible for plastic deformation-an important facet of the problem that has been intensely studied. On the other hand, plastic deformation also results in the creation of new interfaces. While this second facet holds equal importance, it has received comparatively less attention. Further, these two facets, coined interface-driven plasticity and plasticity-driven interfaces, are naturally coupled processes during deformation. The time and length scales characteristic of mesoscale characterization and simulation methods make them well suited for understanding their connection. Along these lines, here we focus on the use of mesoscale characterization and modeling to explore the role that bimetal interfaces play in their own self-development during severe plastic deformation. We demonstrate how mesoscale modeling can provide valuable insight into the design of materials processing techniques with stable interfaces in mind.