Atomistic simulation of deformation induced rotation in Cu-Nb composites

Accumulative roll bonding (ARB) of three copper-niobium (Cu-Nb) nano-composite models is simulated using molecular statics techniques to assess the rotational stability of Cu-Nb interfaces at high strains up to 90% thickness reduction. Crystals strain and rotate under compression, and certain Cu-Nb composites have been shown to reach a steady state of rotation at large rolling reductions. These steady-state rotations correspond to the formation of a preferred interface character between layers. Cumulative rotation of Cu and Nb layers was tracked as a function of strain using a rotation algorithm. A Cu-Nb bicrystal and poly-crystalline model with a {111}<110> Cu// {110}<111> Nb interface character were found to rotate significantly from their initial crystallographic orientation under compression. A Cu-Nb bi-crystal model with a {112}<111>Cu // {112}<110>Nb interface character was found to rotate less when rolled in the transverse direction compared to the typical <111>Cu//<110>Nb rolling direction. Results show that experimentally observed plastic stability of rolled Cu-Nb composites comes from a factor not accounted for in the simulation, like thermally activated dislocation mechanisms. The study refines the current knowledge of plastic stability in Cu-Nb composites.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Materials Science and Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2016

Author dc:creator

• Chesser, Ian (Ian W.)

Advisor dc:contributor.advisor

• Michael Demkowicz.

• Materials Science and Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/104150

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/104150