This is a Nanoscale Interdisciplinary Research Team (NIRT) award in response to a proposal submitted to the Nanoscience and Engineering (NSE) initiative. The research involves multiscale theory and modeling of nanoscale materials. An interdisciplinary limited degrees of freedom (LDF) hierarchy of materials modeling methods that spans multiple length and time scales will be developed for accurately modeling interfaces in nanofeatured materials. The modeling hierarchy, which couples quantum mechanics at the atomic scale, analytic models at the submicron scale and continuum defect modeling above the micron scale, will allow for the accurate control and prediction of processing-structure-property relations from both the atomic up to the macroscale, and from the macroscale down to the atomic scale. The methodology goes beyond embedding subsystems with quantum forces into a continuum environment, and will accurately predict the dominant atomic-level physical mechanisms that lead to macroscale mechanical properties of nanofeatured solids, as well as predictions for macroscale processing conditions that lead to specific target nanostructures and associated properties. Two specific nanofeatured materials will be modeled, with results validated against experiments carried out by NIRT collaborators. The first is nanocrystalline solids, where predicted processing-structure-property relations will be compared to experimental measurements made by Professor Carl Koch at NCSU. The second material is nanodiamond cermet composites, where modeling will be used to predict interface energies, defect propagation rates, and associated macroscale properties, e.g., toughness. Quantum mechanics enters in two ways: (1) to accurately calculate interface properties that are needed in the next level of the hierarchy, and (2) as a framework from which quantum and classical degrees of freedom can be weighted in a localized region of a solid surrounding an embedded nanocomponent, thereby providing a LDF model for quantum systems embedded in a solid environment. The latter role for quantum mechanics is to understand from a fundamental level how the quantum degrees of freedom, and hence the functionality of a quantum-confined structure, like a quantum dot embedded in a solid, may depend on the features of the local environment, and through our mechanics modeling how this local environment in turn depends on macroscale variables such as processing conditions, applied stress, etc. This unique capability, which takes synergistic advantage of the experience of our team in applying quantum theory to engineering systems and in solid mechanics, will facilitate the integrated design of mechanical sensors and related functional structures.
Members of the research team come from two colleges and four departments and have complementary expertise that spans state-of-the-art density functional calculations and quantum formalisms to continuum mechanics-of-materials methodologies. Four partners will provide experimental validation of proposed methods, bring new modeling efforts into the NIRT, and help transition results to industrial and government laboratories. These partners are the International Technology Center in Research Triangle Park, the NASA-Ames Center for Nanotechnology, the Institute for Metals Superplasticity Problems, Ufa, Russia, and Oak Ridge National Laboratory.
Through an interdisciplinary training effort in the form of collaborative research, cross-listed courses, seminars, and interactions with international scholars, a new generation of scientists and engineers will be produced with expertise that is not limited to a single modeling technique, but rather who are trained to attack complicated problems with a broad outlook using methods that transcend traditional barriers between science and engineering disciplines. Outreach will include live and web-based tutorials on nanotechnology, working with high school students and their teachers in summer programs, and participation in national committees on public implications of nanotechnology. Summer students from two local universities, St. Augustine's University and Meredith College, will intern with NIRT research projects. %%% This is a Nanoscale Interdisciplinary Research Team (NIRT) award in response to a proposal submitted to the Nanoscience and Engineering (NSE) initiative. The research involves multiscale theory and modeling of nanoscale materials. An interdisciplinary limited degrees of freedom (LDF) hierarchy of materials modeling methods that spans multiple length and time scales will be developed for accurately modeling interfaces in nanofeatured materials. Members of the research team come from two colleges and four departments and have complementary expertise that spans state-of-the-art density functional calculations and quantum formalisms to continuum mechanics-of-materials methodologies. Four partners will provide experimental validation of proposed methods, bring new modeling efforts into the NIRT, and help transition results to industrial and government laboratories. These partners are the International Technology Center in Research Triangle Park, the NASA-Ames Center for Nanotechnology, the Institute for Metals Superplasticity Problems, Ufa, Russia, and Oak Ridge National Laboratory. Through an interdisciplinary training effort in the form of collaborative research, cross-listed courses, seminars, and interactions with international scholars, a new generation of scientists and engineers will be produced with expertise that is not limited to a single modeling technique, but rather who are trained to attack complicated problems with a broad outlook using methods that transcend traditional barriers between science and engineering disciplines. Outreach will include live and web-based tutorials on nanotechnology, working with high school students and their teachers in summer programs, and participation in national committees on public implications of nanotechnology. Summer students from two local universities, St. Augustine's University and Meredith College, will intern with NIRT research projects. ***
