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dc.contributorVirginia Techen_US
dc.contributor.authorSorensen, M. R.en_US
dc.contributor.authorMishin, Y.en_US
dc.contributor.authorVoter, A. F.en_US
dc.date.accessioned2014-05-07T15:36:53Z
dc.date.available2014-05-07T15:36:53Z
dc.date.issued2000-08-01
dc.identifier.citationSorensen, M. R.; Mishin, Y.; Voter, A. F., "Diffusion mechanisms in Cu grain boundaries," Phys. Rev. B 62, 3658 DOI: http://dx.doi.org/10.1103/PhysRevB.62.3658
dc.identifier.issn0163-1829
dc.identifier.urihttp://hdl.handle.net/10919/47825
dc.description.abstractWe investigate atomic mechanisms of grain boundary (GB) diffusion by combining molecular dynamics (MD), molecular statics, the harmonic approximation to atomic vibrations, and kinetic Monte Carlo (KMC) simulations. The most important aspects of this approach are the basin-constrained implementation of MD and an automated location of transition states using the nudged elastic band method. We study two Sigma=5 [001] symmetric tilt GB's in Cu, with atomic interactions described by an embedded-atom potential. Our simulations demonstrate that GB's support both vacancies and interstitials, and that vacancies can show interesting effects such as delocalization and instability at certain GB sites. Besides simple vacancy-atom exchanges, vacancies move by "long jumps" involving a concerted motion of two atoms. Interstitials move through concerted displacements of two or more atoms. More complex mechanisms (such as ring processes) involving larger groups of atoms have also been found. The obtained point defect formation energies and entropies, as well as their migration rate constants calculated within harmonic transition state theory, are used as input to KMC simulations of GB diffusion. The simulations show that GB diffusion can be dominated by either vacancy or interstitial-related mechanisms depending on the GB structure. The KMC simulations also reveal interesting effects such as temperature-dependent correlation factors and the trapping effect. Using the same simulation approach we study mechanisms of point defect generation in GB's and show that such mechanisms also involve collective transitions.
dc.description.sponsorshipU.S. Department of Energy under Contracts No. W-7405-ENG-36, DE-FG02-99ER45769
dc.format.mimetypeapplication/pdfen_US
dc.language.isoen_US
dc.publisherAmerican Physical Society
dc.subject001 tilt boundariesen_US
dc.subjectMolecular dynamicsen_US
dc.subjectSelf-diffusionen_US
dc.subjectComputer simulationen_US
dc.subjectPoint defectsen_US
dc.subjectAu/ag systemen_US
dc.subjectMigrationen_US
dc.subjectSurfacesen_US
dc.subjectKineticsen_US
dc.subjectMobilityen_US
dc.subjectPhysicsen_US
dc.subjectCondensed matteren_US
dc.titleDiffusion mechanisms in Cu grain boundariesen_US
dc.typeArticle - Refereeden_US
dc.contributor.departmentMaterials Science and Engineering (MSE)en_US
dc.identifier.urlhttp://journals.aps.org/prb/abstract/10.1103/PhysRevB.62.3658
dc.date.accessed2014-04-23
dc.title.serialPhysical Review B
dc.identifier.doihttps://doi.org/10.1103/PhysRevB.62.3658
dc.type.dcmitypeTexten_US


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