{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/19462"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/19462","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Diffusion along twist grain boundaries in copper","abstract":"U of I Only","abstract_html":"U of I Only","abstract_has_math":false,"creators":["Nomura, Miki"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Materials Science and Engineering","degree_department":null,"school":null,"contributors":["Adams, James B."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T12:08:17Z","date_published":"2011-05-07T12:08:17Z","updated_at":"2026-07-22T22:25:14Z","subjects":["Engineering, Materials Science"],"languages":["eng"],"rights":["Copyright 1996 Nomura, Miki"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9625174","(UMI)AAI9625174"],"render_values":[{"text":"AAI9625174","href":null,"code":true},{"text":"(UMI)AAI9625174","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/19462","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Adams, James B."]},{"key":"dc:creator","label":"Author","values":["Nomura, Miki"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T12:08:17Z","10000-01-01","1996"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Materials Science and Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Engineering, Materials Science"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 1996 Nomura, Miki"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9625174","(UMI)AAI9625174","http://hdl.handle.net/2142/19462"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["U of I Only","Diffusion along twist grain boundaries was studied using the Embedded Atom Method (EAM). Six (100) twist grain boundaries (8.79$\\sp\\circ$-43.6$\\sp\\circ$) in Copper were investigated using energy minimization. Both vacancy and interstitial mechanisms were considered. Vacancy formation energies in all possible sites were calculated (0.14-0.76eV) and found to be directly related to the degree of coincidence with the neighboring crystal planes. The optimal migration paths were found to coincide with the screw dislocations which comprise the boundary. Vacancy migration energies were found to be low (0.02-0.52eV). The activation energies for self-diffusion at the boundaries were found to be less than half of the bulk value (2.07eV). Interstitial formation energies were found to be lower (0.26-0.78eV) than in the bulk also and migration energies were found to be comparable (0.01eV-0.24eV) to the bulk values (0.09eV). The vacancy mechanism was favored for low angle boundaries and the interstitial mechanism was favored for high angle boundaries. The total diffusion rate was calculated and agreed with the experimental value obtained from studies of polycrystalline Cu, and also, with experimental value for specific twist boundaries of Zn/Al. Molecular dynamics (MD) simulation of diffusion along high ($\\Sigma$5 36.87$\\sp\\circ$) twist grain boundaries were carried out. Both ideal structures and boundaries with excess vacancies or excess interstitials were studied. A ring mechanism was observed during the simulation, but it did not contribute to long range diffusion. The mean square displacement of the atoms and defects were used to calculate the diffusion rate of the defects, and the results were in good agreement with the molecular statics calculations.","Made available in DSpace on 2011-05-07T12:08:17Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9625174.pdf: 4826977 bytes, checksum: bfaff882ce2727ca78d8d10abb69255f (MD5) Previous issue date: 1996","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:37:07Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:15:12-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission"]},{"key":"dc:title","label":"Title","values":["Diffusion along twist grain boundaries in copper"]}]}],"canonical_facts":{"dc:contributor":["Adams, James B."],"dc:creator":["Nomura, Miki"],"dc:date":["2011-05-07T12:08:17Z","10000-01-01","1996"],"dc:description":["U of I Only","Diffusion along twist grain boundaries was studied using the Embedded Atom Method (EAM). Six (100) twist grain boundaries (8.79$\\sp\\circ$-43.6$\\sp\\circ$) in Copper were investigated using energy minimization. Both vacancy and interstitial mechanisms were considered. Vacancy formation energies in all possible sites were calculated (0.14-0.76eV) and found to be directly related to the degree of coincidence with the neighboring crystal planes. The optimal migration paths were found to coincide with the screw dislocations which comprise the boundary. Vacancy migration energies were found to be low (0.02-0.52eV). The activation energies for self-diffusion at the boundaries were found to be less than half of the bulk value (2.07eV). Interstitial formation energies were found to be lower (0.26-0.78eV) than in the bulk also and migration energies were found to be comparable (0.01eV-0.24eV) to the bulk values (0.09eV). The vacancy mechanism was favored for low angle boundaries and the interstitial mechanism was favored for high angle boundaries. The total diffusion rate was calculated and agreed with the experimental value obtained from studies of polycrystalline Cu, and also, with experimental value for specific twist boundaries of Zn/Al. Molecular dynamics (MD) simulation of diffusion along high ($\\Sigma$5 36.87$\\sp\\circ$) twist grain boundaries were carried out. Both ideal structures and boundaries with excess vacancies or excess interstitials were studied. A ring mechanism was observed during the simulation, but it did not contribute to long range diffusion. The mean square displacement of the atoms and defects were used to calculate the diffusion rate of the defects, and the results were in good agreement with the molecular statics calculations.","Made available in DSpace on 2011-05-07T12:08:17Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9625174.pdf: 4826977 bytes, checksum: bfaff882ce2727ca78d8d10abb69255f (MD5) Previous issue date: 1996","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:37:07Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:15:12-05:00 Original Data Group with Access UIUC Users [automated] Release Date: none Reason: ETDs are only available to UIUC Users without author permission","ETDs are only available to UIUC Users without author permission"],"dc:identifier":["AAI9625174","(UMI)AAI9625174","http://hdl.handle.net/2142/19462"],"dc:language":["eng"],"dc:rights":["Copyright 1996 Nomura, Miki"],"dc:subject":["Engineering, Materials Science"],"dc:title":["Diffusion along twist grain boundaries in copper"],"dc:type":["text"],"thesis:degree_discipline":["Materials Science and Engineering"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:25:14Z"}