{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/99441"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/99441","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Healing of complex damage modes in model composites","abstract":"Self-healing has potential to extend the usable lifetime of composite materials. Introducing self-healing systems to fiber reinforced composites has proven to be difficult due to the high temperatures and pressures of processing as well as the requirement that the delivery scheme for the healing agent must exist in the interstitial regions between fibers. Additionally, assessment of self-healing performance for composites poses a challenge as many damage modes occur during composite failure including matrix cracking and fiber-matrix debonding. In this thesis, a tow-level model composite test is developed with a view towards simplifying characterization and improving understanding of capsule-based self-healing in fiber reinforced composites. The tow-level test is intended to allow for testing of potential healing without requiring manufacture of a complex composite panel. A modified compact tension is developed with a carbon fiber tow running orthogonally to the advancing crack plane. Initial testing of a non-healing control system reveals that the tow can survive crack propagation and that debonding of the matrix and tow occurs. Additionally, the size of the debonding damage correlates to the magnitude of energy released. Healing studies utilized a phase-separated thermoplastic-epoxy matrix with solvent filled microcapsules. Initial reference tests with the matrix but no microcapsules showed high healing efficiency of over 100% when the solvent was injected manually. However, no mechanical healing response could be observed when microcapsules were incorporated to deliver healing agent to the crack. Attempts were made at altering the healing agent delivery scheme as well as the healing conditions to increase healing response, but no combination of conditions was shown to be suitable for self-healing to occur.","abstract_html":"Self-healing has potential to extend the usable lifetime of composite materials. Introducing self-healing systems to fiber reinforced composites has proven to be difficult due to the high temperatures and pressures of processing as well as the requirement that the delivery scheme for the healing agent must exist in the interstitial regions between fibers. Additionally, assessment of self-healing performance for composites poses a challenge as many damage modes occur during composite failure including matrix cracking and fiber-matrix debonding. In this thesis, a tow-level model composite test is developed with a view towards simplifying characterization and improving understanding of capsule-based self-healing in fiber reinforced composites. The tow-level test is intended to allow for testing of potential healing without requiring manufacture of a complex composite panel. A modified compact tension is developed with a carbon fiber tow running orthogonally to the advancing crack plane. Initial testing of a non-healing control system reveals that the tow can survive crack propagation and that debonding of the matrix and tow occurs. Additionally, the size of the debonding damage correlates to the magnitude of energy released. Healing studies utilized a phase-separated thermoplastic-epoxy matrix with solvent filled microcapsules. Initial reference tests with the matrix but no microcapsules showed high healing efficiency of over 100% when the solvent was injected manually. However, no mechanical healing response could be observed when microcapsules were incorporated to deliver healing agent to the crack. Attempts were made at altering the healing agent delivery scheme as well as the healing conditions to increase healing response, but no combination of conditions was shown to be suitable for self-healing to occur.","abstract_has_math":false,"creators":["Lauer, Andrew Robert"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"M.S.","degree_level":"Thesis","degree_discipline":"Materials Science & Engr","degree_department":null,"school":null,"contributors":["Sottos, Nancy R."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2018,"date_issued":"2018-03-13T15:49:22Z","date_published":"2018-03-13T15:49:22Z","updated_at":"2026-07-22T22:24:37Z","subjects":["Composites","Self-healing","Model composites","Microcapsules","Carbon fiber"],"languages":["en"],"rights":["Copyright 2017 Andrew R. Lauer"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"http://hdl.handle.net/2142/99441","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Sottos, Nancy R."]},{"key":"dc:creator","label":"Author","values":["Lauer, Andrew Robert"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2018-03-13T15:49:22Z","2017-12-15","2017-12"]},{"key":"dc:type","label":"Dc Type","values":["text"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Materials Science & Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Thesis"]},{"key":"thesis:degree_name","label":"Degree Name","values":["M.S."]},{"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":["Composites","Self-healing","Model composites","Microcapsules","Carbon fiber"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2017 Andrew R. Lauer"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["http://hdl.handle.net/2142/99441"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Self-healing has potential to extend the usable lifetime of composite materials. Introducing self-healing systems to fiber reinforced composites has proven to be difficult due to the high temperatures and pressures of processing as well as the requirement that the delivery scheme for the healing agent must exist in the interstitial regions between fibers. Additionally, assessment of self-healing performance for composites poses a challenge as many damage modes occur during composite failure including matrix cracking and fiber-matrix debonding. In this thesis, a tow-level model composite test is developed with a view towards simplifying characterization and improving understanding of capsule-based self-healing in fiber reinforced composites. The tow-level test is intended to allow for testing of potential healing without requiring manufacture of a complex composite panel. A modified compact tension is developed with a carbon fiber tow running orthogonally to the advancing crack plane. Initial testing of a non-healing control system reveals that the tow can survive crack propagation and that debonding of the matrix and tow occurs. Additionally, the size of the debonding damage correlates to the magnitude of energy released. Healing studies utilized a phase-separated thermoplastic-epoxy matrix with solvent filled microcapsules. Initial reference tests with the matrix but no microcapsules showed high healing efficiency of over 100% when the solvent was injected manually. However, no mechanical healing response could be observed when microcapsules were incorporated to deliver healing agent to the crack. Attempts were made at altering the healing agent delivery scheme as well as the healing conditions to increase healing response, but no combination of conditions was shown to be suitable for self-healing to occur.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2018-03-13 without embargo terms","The student, Andrew Lauer, accepted the attached license on 2017-12-15 at 10:16.","The student, Andrew Lauer, submitted this Thesis for approval on 2017-12-15 at 10:25.","This Thesis was approved for publication on 2017-12-15 at 13:11.","DSpace SAF Submission Ingestion Package generated from Vireo submission #11994 on 2018-03-13 at 10:12:55","Made available in DSpace on 2018-03-13T15:49:22Z (GMT). No. of bitstreams: 2 LAUER-THESIS-2017.pdf: 2132147 bytes, checksum: 6bef9bf086cadfec6c10b108408ad1b1 (MD5) LICENSE.txt: 4209 bytes, checksum: b79b185901c0d630fb09f411b7372f78 (MD5) Previous issue date: 2017-12-15"]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Healing of complex damage modes in model composites"]}]}],"canonical_facts":{"dc:contributor":["Sottos, Nancy R."],"dc:creator":["Lauer, Andrew Robert"],"dc:date":["2018-03-13T15:49:22Z","2017-12-15","2017-12"],"dc:description":["Self-healing has potential to extend the usable lifetime of composite materials. Introducing self-healing systems to fiber reinforced composites has proven to be difficult due to the high temperatures and pressures of processing as well as the requirement that the delivery scheme for the healing agent must exist in the interstitial regions between fibers. Additionally, assessment of self-healing performance for composites poses a challenge as many damage modes occur during composite failure including matrix cracking and fiber-matrix debonding. In this thesis, a tow-level model composite test is developed with a view towards simplifying characterization and improving understanding of capsule-based self-healing in fiber reinforced composites. The tow-level test is intended to allow for testing of potential healing without requiring manufacture of a complex composite panel. A modified compact tension is developed with a carbon fiber tow running orthogonally to the advancing crack plane. Initial testing of a non-healing control system reveals that the tow can survive crack propagation and that debonding of the matrix and tow occurs. Additionally, the size of the debonding damage correlates to the magnitude of energy released. Healing studies utilized a phase-separated thermoplastic-epoxy matrix with solvent filled microcapsules. Initial reference tests with the matrix but no microcapsules showed high healing efficiency of over 100% when the solvent was injected manually. However, no mechanical healing response could be observed when microcapsules were incorporated to deliver healing agent to the crack. Attempts were made at altering the healing agent delivery scheme as well as the healing conditions to increase healing response, but no combination of conditions was shown to be suitable for self-healing to occur.","Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2018-03-13 without embargo terms","The student, Andrew Lauer, accepted the attached license on 2017-12-15 at 10:16.","The student, Andrew Lauer, submitted this Thesis for approval on 2017-12-15 at 10:25.","This Thesis was approved for publication on 2017-12-15 at 13:11.","DSpace SAF Submission Ingestion Package generated from Vireo submission #11994 on 2018-03-13 at 10:12:55","Made available in DSpace on 2018-03-13T15:49:22Z (GMT). No. of bitstreams: 2 LAUER-THESIS-2017.pdf: 2132147 bytes, checksum: 6bef9bf086cadfec6c10b108408ad1b1 (MD5) LICENSE.txt: 4209 bytes, checksum: b79b185901c0d630fb09f411b7372f78 (MD5) Previous issue date: 2017-12-15"],"dc:format":["application/pdf"],"dc:identifier":["http://hdl.handle.net/2142/99441"],"dc:language":["en"],"dc:rights":["Copyright 2017 Andrew R. Lauer"],"dc:subject":["Composites","Self-healing","Model composites","Microcapsules","Carbon fiber"],"dc:title":["Healing of complex damage modes in model composites"],"dc:type":["text"],"thesis:degree_discipline":["Materials Science & Engr"],"thesis:degree_level":["Thesis"],"thesis:degree_name":["M.S."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:37Z"}