Abstract
dc:description.abstractA study of the stability of bicontinuous nanoporous metals is presented. Atomic scale simulations are used to probe the dominant mechanisms of geometric relaxation in these materials. A method is presented for generating model bicontinuous metal / void structures for use in atomistic simulations of bicontinuous nanoporous solids. The structures are generated with periodic boundary conditions using a phase-field model to simulate the spinodal decomposition of an ideal system. One phase in the model is then associated with the pore volume while the other phase is associated with the metal ligaments. Small angle neutron scattering was used to quantitatively compare experimental samples to those generated by the phase field method. EAM results using model structures with experimentally accessible length scales are presented which demonstrate the potential of such simulations in understanding the behavior of nanoporous metals. Simulated relaxations of these structures, as well as the relaxation of model spherical clusters, indicate that the surface relaxation effect dominates the overall dimensional relaxation of np-metals post processing. Capillary effects play a secondary role in the overall relaxation. The simulation results presented also identify a maximum surface area to volume ratio necessary to maintain mechanical stability beyond which the pore structure collapses.
Degree
thesis:*- Name thesis:degree_name
- Ph. D.
- Level thesis:degree_level
- doctoral
- Discipline thesis:degree_discipline
- Materials Science and Engineering
- Department dc:contributor.department
- Materials Science and Engineering
- Grantor dc:publisher
- Virginia Tech
- Year dc:date.issued
- 2006
Author and committee
dc:creator, dc:contributor.*- Author dc:creator
-
- Crowson, Douglas A.
- Chairs dc:contributor.committeechair
-
- Corcoran, Sean G.
- Farkas, Diana
- Committee members dc:contributor.committeemember
-
- Reynolds, William T. Jr.
- Batra, Romesh C.
- Wang, Yu
Subjects
dc:subject × 5Rights
dc:rights- Statement dc:rights
-
- In Copyright
- Licence dc:rights.uri
Identifiers
dc:identifier.*- Dc Identifier Other
- etd-06242006-163956
- OAI identifier oai:identifier
- oai:vtechworks.lib.vt.edu:10919/28111