Get access

Interface-Driven Plasticity: The Presence of an Interface Affected Zone in Metallic Lamellar Composites

Authors


  • J. S. C. and R. J. M. acknowledge the financial support provided by the Los Alamos National Laboratory Directed Research and Development (LDRD) project 20140348ER. J. R. M., I. J. B., and N. A. M. gratefully acknowledge support by the Center for Materials at Irradiation and Mechanical Extremes, an Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences under Award Number 2008LANL1026. Los Alamos National Laboratory is operated by Los Alamos National Security LLC under DOE Contract DEAC5206NA25396. Electron microscopy was performed at the Los Alamos Electron Microscopy Laboratory.

Abstract

Large strain deformation is used to make fine nanolayered two-phase composites from stacks of conventional polycrystalline sheets. The final materials made by this technique possess a crystallographically highly oriented structure containing nearly atomically perfect interfaces prevailing ubiquitously throughout the material. How this ordered structure evolves with strain from the coarser, more disordered state is not known. Here, using microstructural analysis and computational modeling, we discover a local interface-affected zone (IAZ) possessing the same crystallographically sharp structure in coarse layered composites as the final nanolayered composites. This means that this strongly oriented interface “zone” survives the mechanical work and overtakes the structure as it refines to the nanoscale. In essence, through the formation of this interface zone, the crossover to a highly oriented nanostructure occurs. Using microstructural analysis and crystal plasticity simulations, we show that the IAZ is a consequence of slip accommodation at the interface. This insight is valuable for developing processing strategies for superior interface-dominated materials.

Get access to the full text of this article

Ancillary