{"id":{"repo_id":"ohiolink","oai_identifier":"oai:etd.ohiolink.edu:osu1363615565"},"canonical_url":"https://search.dev.ndltd.org/etd/ohiolink/oai:etd.ohiolink.edu:osu1363615565","repository":{"repo_id":"ohiolink","name":"OhioLINK","base_url":"https://etd.ohiolink.edu/acprod/odb_etd/ws/oai/oai"},"display":{"title":"Dislocation Modeling of Mechanical Properties of Nanolayered Composite Materials","abstract":"Nanoscale multilayered materials exhibit extraordinary strength, due to the abilityof these systems to confine slip to individual layers. This work adopts a premisesuggested by embedded atom simulations in copper-niobium multilayers that the tensileyield strength is determined approximately by the critical applied stress to eliminate thecompressive biaxial stress in alternating layers of the composite. Yield strength maps areconstructed for nanoscale multilayered composites consisting of alternating layer phasesin which the volume fraction of the phases, bilayer thickness, and ratio of in-plane stressfree lattice parameters of the two phases are regarded as variables. Also, the degree of coherency of the interfaces and the internal biaxial stress state in each layer prior to loading are predicted as a function of these variables. The results suggest that decreasing bilayer thickness is a limited approach to increasing the biaxial yield strength of nanolayered composites.The consequences of growing multilayered thin films on substrates of finite sizeare also investigated. Substrates with lattice parameters less than or greater than those ofeither constituent, or possessing a lattice parameter between either of the constituentphases, were examined, with mixed results. Internal stress states of attached and detached multilayers were calculated and compared to the detached and heat-treated stress states determined as described in the proceeding paragraph. Attached multilayers showed masking effects that changed depending on the lattice parameter of the substrate. Detached multilayers consisted of internal stress contours with a similar shape of those displayed by the detached and heat-treated multilayers. The multilayer strength maps of each state revealed interesting results. The attached and detached strength maps were virtually indistinguishable, but when compared to the detached and heat-treated strength maps were very different quantitatively. The detached and heat-treated multilayers had strength gains that were 12% to 40% over the attached and detached conditions, with smaller gains occurring as the volume fraction of phase 1 was increased.The effects of adding structural resistance to the model were also examined. The strength maps for each condition showed an increase in overall multilayer strength, with the greatest increase occurring at small volume fractions of phase 1. This is in accordance with the values that resulted from heat-treating the multilayers.Comparisons of the theoretical results calculated by the model to experimentaldata collected by external scientists are also made, including changes and additions to the model that would create better agreement between the two data sets.","abstract_html":"Nanoscale multilayered materials exhibit extraordinary strength, due to the abilityof these systems to confine slip to individual layers. This work adopts a premisesuggested by embedded atom simulations in copper-niobium multilayers that the tensileyield strength is determined approximately by the critical applied stress to eliminate thecompressive biaxial stress in alternating layers of the composite. Yield strength maps areconstructed for nanoscale multilayered composites consisting of alternating layer phasesin which the volume fraction of the phases, bilayer thickness, and ratio of in-plane stressfree lattice parameters of the two phases are regarded as variables. Also, the degree of coherency of the interfaces and the internal biaxial stress state in each layer prior to loading are predicted as a function of these variables. The results suggest that decreasing bilayer thickness is a limited approach to increasing the biaxial yield strength of nanolayered composites.The consequences of growing multilayered thin films on substrates of finite sizeare also investigated. Substrates with lattice parameters less than or greater than those ofeither constituent, or possessing a lattice parameter between either of the constituentphases, were examined, with mixed results. Internal stress states of attached and detached multilayers were calculated and compared to the detached and heat-treated stress states determined as described in the proceeding paragraph. Attached multilayers showed masking effects that changed depending on the lattice parameter of the substrate. Detached multilayers consisted of internal stress contours with a similar shape of those displayed by the detached and heat-treated multilayers. The multilayer strength maps of each state revealed interesting results. The attached and detached strength maps were virtually indistinguishable, but when compared to the detached and heat-treated strength maps were very different quantitatively. The detached and heat-treated multilayers had strength gains that were 12% to 40% over the attached and detached conditions, with smaller gains occurring as the volume fraction of phase 1 was increased.The effects of adding structural resistance to the model were also examined. The strength maps for each condition showed an increase in overall multilayer strength, with the greatest increase occurring at small volume fractions of phase 1. This is in accordance with the values that resulted from heat-treating the multilayers.Comparisons of the theoretical results calculated by the model to experimentaldata collected by external scientists are also made, including changes and additions to the model that would create better agreement between the two data sets.","abstract_has_math":false,"creators":["Lamm, Adrienne Valerie"],"institution":"The Ohio State University","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Materials Science and Engineering","degree_department":null,"school":null,"contributors":["Anderson, Peter"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2004,"date_issued":"2004","date_published":"2004","updated_at":"2026-07-24T03:37:01Z","subjects":["Engineering","Materials Science"],"languages":["English"],"rights":["unrestricted","This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws."],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://rave.ohiolink.edu/etdc/view?acc_num=osu1363615565","outbound_label":"Repository record","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Anderson, Peter"]},{"key":"dc:creator","label":"Author","values":["Lamm, Adrienne Valerie"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2004"]},{"key":"dc:publisher","label":"Institution","values":["The Ohio State University / OhioLINK"]},{"key":"dc:type","label":"Dc Type","values":["Electronic Thesis or Dissertation"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Materials Science and Engineering"]},{"key":"thesis:degree_level","label":"Degree Level","values":["masters"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Master of Science"]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["The Ohio State University"]}]},{"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":["English"]},{"key":"dc:rights","label":"Dc Rights","values":["unrestricted","This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws."]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://rave.ohiolink.edu/etdc/view?acc_num=osu1363615565"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Nanoscale multilayered materials exhibit extraordinary strength, due to the abilityof these systems to confine slip to individual layers. This work adopts a premisesuggested by embedded atom simulations in copper-niobium multilayers that the tensileyield strength is determined approximately by the critical applied stress to eliminate thecompressive biaxial stress in alternating layers of the composite. Yield strength maps areconstructed for nanoscale multilayered composites consisting of alternating layer phasesin which the volume fraction of the phases, bilayer thickness, and ratio of in-plane stressfree lattice parameters of the two phases are regarded as variables. Also, the degree of coherency of the interfaces and the internal biaxial stress state in each layer prior to loading are predicted as a function of these variables. The results suggest that decreasing bilayer thickness is a limited approach to increasing the biaxial yield strength of nanolayered composites.The consequences of growing multilayered thin films on substrates of finite sizeare also investigated. Substrates with lattice parameters less than or greater than those ofeither constituent, or possessing a lattice parameter between either of the constituentphases, were examined, with mixed results. Internal stress states of attached and detached multilayers were calculated and compared to the detached and heat-treated stress states determined as described in the proceeding paragraph. Attached multilayers showed masking effects that changed depending on the lattice parameter of the substrate. Detached multilayers consisted of internal stress contours with a similar shape of those displayed by the detached and heat-treated multilayers. The multilayer strength maps of each state revealed interesting results. The attached and detached strength maps were virtually indistinguishable, but when compared to the detached and heat-treated strength maps were very different quantitatively. The detached and heat-treated multilayers had strength gains that were 12% to 40% over the attached and detached conditions, with smaller gains occurring as the volume fraction of phase 1 was increased.The effects of adding structural resistance to the model were also examined. The strength maps for each condition showed an increase in overall multilayer strength, with the greatest increase occurring at small volume fractions of phase 1. This is in accordance with the values that resulted from heat-treating the multilayers.Comparisons of the theoretical results calculated by the model to experimentaldata collected by external scientists are also made, including changes and additions to the model that would create better agreement between the two data sets."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf","p.148","3.62 MB"]},{"key":"dc:title","label":"Title","values":["Dislocation Modeling of Mechanical Properties of Nanolayered Composite Materials"]}]}],"canonical_facts":{"dc:contributor":["Anderson, Peter"],"dc:creator":["Lamm, Adrienne Valerie"],"dc:date":["2004"],"dc:description":["Nanoscale multilayered materials exhibit extraordinary strength, due to the abilityof these systems to confine slip to individual layers. This work adopts a premisesuggested by embedded atom simulations in copper-niobium multilayers that the tensileyield strength is determined approximately by the critical applied stress to eliminate thecompressive biaxial stress in alternating layers of the composite. Yield strength maps areconstructed for nanoscale multilayered composites consisting of alternating layer phasesin which the volume fraction of the phases, bilayer thickness, and ratio of in-plane stressfree lattice parameters of the two phases are regarded as variables. Also, the degree of coherency of the interfaces and the internal biaxial stress state in each layer prior to loading are predicted as a function of these variables. The results suggest that decreasing bilayer thickness is a limited approach to increasing the biaxial yield strength of nanolayered composites.The consequences of growing multilayered thin films on substrates of finite sizeare also investigated. Substrates with lattice parameters less than or greater than those ofeither constituent, or possessing a lattice parameter between either of the constituentphases, were examined, with mixed results. Internal stress states of attached and detached multilayers were calculated and compared to the detached and heat-treated stress states determined as described in the proceeding paragraph. Attached multilayers showed masking effects that changed depending on the lattice parameter of the substrate. Detached multilayers consisted of internal stress contours with a similar shape of those displayed by the detached and heat-treated multilayers. The multilayer strength maps of each state revealed interesting results. The attached and detached strength maps were virtually indistinguishable, but when compared to the detached and heat-treated strength maps were very different quantitatively. The detached and heat-treated multilayers had strength gains that were 12% to 40% over the attached and detached conditions, with smaller gains occurring as the volume fraction of phase 1 was increased.The effects of adding structural resistance to the model were also examined. The strength maps for each condition showed an increase in overall multilayer strength, with the greatest increase occurring at small volume fractions of phase 1. This is in accordance with the values that resulted from heat-treating the multilayers.Comparisons of the theoretical results calculated by the model to experimentaldata collected by external scientists are also made, including changes and additions to the model that would create better agreement between the two data sets."],"dc:format":["application/pdf","p.148","3.62 MB"],"dc:identifier":["http://rave.ohiolink.edu/etdc/view?acc_num=osu1363615565"],"dc:language":["English"],"dc:publisher":["The Ohio State University / OhioLINK"],"dc:rights":["unrestricted","This thesis or dissertation is protected by copyright: all rights reserved. It may not be copied or redistributed beyond the terms of applicable copyright laws."],"dc:subject":["Engineering","Materials Science"],"dc:title":["Dislocation Modeling of Mechanical Properties of Nanolayered Composite Materials"],"dc:type":["Electronic Thesis or Dissertation"],"thesis:degree_discipline":["Materials Science and Engineering"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["The Ohio State University"]},"updated_at":"2026-07-24T03:37:01Z"}