NSF-Europe: Computer Simulation of Fracture and Deformation Behavior of Nanocrystalline Metallic Materials

Virginia Polytechnic Institute And State University, Blacksburg VA

Investigators

Abstract

This NSF-Europe award supports international collaborative research involving the Paul Scherrer Institute, Switzerland. The PI will study of the mechanical behavior of nanocrystalline metallic materials using computer simulation models at the atomic scale. The research program will build on an initial collaboration that focussed on modeling the structure of general, randomly generated grain boundaries in these materials and included a fracture response study of nanocrystalline Ni. The PI will build on this past work and utilize advances in computer technology to carry out a more realistic study of the behavior of fcc metals with full three-dimensional treatments of the polycrystalline structure as well as internal defect structures in a wide range of grain sizes. The collaboration involves performing atomic level computer simulations of the deformation and fracture behavior of realistic three-dimensional models of various nanocrystalline fcc metals. The effects of impurity elements on the deformation and fracture properties will be studied in detail. The PI will use a multi-scale approach, starting with first principle calculations that are used as input in the development of empirical interatomic force laws, continuing with molecular dynamics simulations of the response to loading of multimillion atom simulation blocks. The work will be closely linked with experiments related to the development of new nanostructured materials. The research will address fundamental questions in the area of fracture and deformation of nanocrystalline materials and will contribute to basic understanding of the particular behavior of these materials under loading and addressing the basic plasticity mechanisms operating in the crack tip region. The simulation studies will be designed to critically study the effects of various types of interfaces and interface defects on the mechanical response of the nanostructured material containing a large amount of interface material. Enhanced understanding in these areas will likely impact the design of new nanostructured materials. This activity also involves graduate level education and exposure to the broader international scientific community. This NSF project is co-funded by the Office of Multidisciplinary Activities, the Division of Materials Research, and the International Office (Western Europe) as a Cooperative Activity in Materials Research between the NSF and Europe (NSF 02-135). This project is being carried out in collaboration with the Paul Scherrer Institute, Switzerland. The counterpart project is funded by the Swiss National Science Foundation. %%% This NSF-Europe award supports international collaborative research involving the Paul Scherrer Institute, Switzerland. The PI will study of the mechanical behavior of nanocrystalline metallic materials using computer simulation models at the atomic scale. The research program will build on an initial collaboration that focussed on modeling the structure of general, randomly generated grain boundaries in these materials. The PI will build on this past work and utilize advances in computer technology to carry out a more realistic study of the behavior of fcc metals with full three-dimensional treatments of the polycrystalline structure as well as internal defect structures in a wide range of grain sizes. The collaboration involves performing atomic level computer simulations of the deformation and fracture behavior of realistic three-dimensional models of various nanocrystalline fcc metals. The effects of impurity elements on the deformation and fracture properties will be studied in detail. The work will be closely linked with experiments related to the development of new nanostructured materials. The proposed research will address fundamental questions in the area of fracture and deformation of nanocrystalline materials. The simulation studies will be designed to critically study the effects of various types of interfaces and interface defects on the mechanical response of the nanomaterial containing a large amount of interface material. Enhanced understanding or mechanical response at the atomic level will likely impact the design of new nanostructured materials. This activity also involves graduate level education and exposure to the broader international scientific community. This NSF project is co-funded by the Office of Multidisciplinary Activities, the Division of Materials Research, and the International Office (Western Europe) as a Cooperative Activity in Materials Research between the NSF and Europe (NSF 02-135). This project is being carried out in collaboration with the Paul Scherrer Institute, Switzerland. The counterpart project is funded by the Swiss National Science Foundation. The counterpart project is funded by the Swiss National Science Foundation. ***