{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/22470"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/22470","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Defect and deformation studies in transition metal trialuminide compounds","abstract":"Defect studies have been performed on the intermetallic compounds $\\rm Al\\sb3Ti$, $\\rm Al\\sb3V$ and $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$ which were deformed at elevated temperatures. Test materials were prepared via the rapid solidification route. TEM characterizations indicated that the microstructure of the asatomized Al-25at.%Ti alloy powder consisted of primary dendrites of the $\\rm Al\\sb3Ti$ phase (DO$\\sb{22}$ structure) and $\\alpha$-aluminum. The as-atomized Al-25at.%V alloy exhibited a microstructure composed of primary $\\rm Al\\sb8V\\sb5$ dendrites with interdendritic $\\rm Al\\sb3V$ (DO$\\sb{22}$) and $\\alpha$-aluminum. The Al-8at.%Ni-25at.% Ti alloy exhibited dendrites of $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$(L1$\\sb2$) and small $\\rm Al\\sb3Ni\\sb2$ particles.","abstract_html":"Defect studies have been performed on the intermetallic compounds $\\rm Al\\sb3Ti$, $\\rm Al\\sb3V$ and $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$ which were deformed at elevated temperatures. Test materials were prepared via the rapid solidification route. TEM characterizations indicated that the microstructure of the asatomized Al-25at.%Ti alloy powder consisted of primary dendrites of the $\\rm Al\\sb3Ti$ phase (DO$\\sb{22}$ structure) and <span class=\"etd-inline-math\">&alpha;</span>-aluminum. The as-atomized Al-25at.%V alloy exhibited a microstructure composed of primary $\\rm Al\\sb8V\\sb5$ dendrites with interdendritic $\\rm Al\\sb3V$ (DO$\\sb{22}$) and <span class=\"etd-inline-math\">&alpha;</span>-aluminum. The Al-8at.%Ni-25at.% Ti alloy exhibited dendrites of $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$(L1$\\sb2$) and small $\\rm Al\\sb3Ni\\sb2$ particles.","abstract_has_math":true,"creators":["Wheeler, Robert, IV"],"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":["Fraser, Hamish L."],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2011,"date_issued":"2011-05-07T13:40:54Z","date_published":"2011-05-07T13:40:54Z","updated_at":"2026-07-22T22:25:20Z","subjects":["Engineering, Metallurgy","Engineering, Materials Science"],"languages":["eng"],"rights":["Copyright 1990 Wheeler, Robert, IV"],"rights_urls":[],"identifier_entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9026350","(UMI)AAI9026350"],"render_values":[{"text":"AAI9026350","href":null,"code":true},{"text":"(UMI)AAI9026350","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/2142/22470","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Fraser, Hamish L."]},{"key":"dc:creator","label":"Author","values":["Wheeler, Robert, IV"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2011-05-07T13:40:54Z","10000-01-01","1990"]},{"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, Metallurgy","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 1990 Wheeler, Robert, IV"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["AAI9026350","(UMI)AAI9026350","http://hdl.handle.net/2142/22470"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Defect studies have been performed on the intermetallic compounds $\\rm Al\\sb3Ti$, $\\rm Al\\sb3V$ and $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$ which were deformed at elevated temperatures. Test materials were prepared via the rapid solidification route. TEM characterizations indicated that the microstructure of the asatomized Al-25at.%Ti alloy powder consisted of primary dendrites of the $\\rm Al\\sb3Ti$ phase (DO$\\sb{22}$ structure) and $\\alpha$-aluminum. The as-atomized Al-25at.%V alloy exhibited a microstructure composed of primary $\\rm Al\\sb8V\\sb5$ dendrites with interdendritic $\\rm Al\\sb3V$ (DO$\\sb{22}$) and $\\alpha$-aluminum. The Al-8at.%Ni-25at.% Ti alloy exhibited dendrites of $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$(L1$\\sb2$) and small $\\rm Al\\sb3Ni\\sb2$ particles.","The consolidated Al-25at.%Ti alloy contained $\\rm Al\\sb3Ti$ with numerous small particles. Three types of second phases were noted: TiAl particles, oxide streamers at prior particle boundaries; and small TiC particles within certain grains. In the consolidated Al-25at.%V powder, large $\\rm Al\\sb8V\\sb5$ particles were identified within a matrix of $\\rm Al\\sb3V$. The Al-8at.%Ni-25at.%Ti alloy contained $\\rm Al\\sb2NiTi$ particles (fcc, a$\\sb0$ = 11.94A) in a matrix of $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$.","Compression testing was carried out at 300$\\sp\\circ$C, 600$\\sp\\circ$C and 800$\\sp\\circ$C. The weak-beam darkfield technique was employed to determine the Burgers vector, slip plane and dissociation reactions of dislocations responsible for plastic deformation.","In $\\rm Al\\sb3Ti$, microtwins on the close packed $\\{112)$ planes formed by the repeated passage of 1/6 $<$ 111) partial dislocations on successive $\\{112)$ planes were identified. Partial dislocations with b = 1/2 $<$ 110) which bound APB's on the (001) plane were also characterized at 300$\\sp\\circ$C and 600$\\sp\\circ$C. Dislocations with b = $<$100) were found to glide on (001) and shown to climb at the higher temperatures ($\\geq$600$\\sp\\circ$C). $\\rm Al\\sb3V$ appears to deform by glide of b = $<$110) dislocation son the $\\{112)$ planes. At 800$\\sp\\circ$C, again climbing $<$100) dislocations were found. In $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$, dislocation glide of the type $\\langle 110\\rangle\\{111\\}$ was identified. At 300$\\sp\\circ$C, the dislocations were undissociated, while at 600$\\sp\\circ$C and 800$\\sp\\circ$C, considerable APB-type dissociation on the $\\{001\\}$ planes was noted.","Defect structures in the two DO$\\sb{22}$ compounds have been explained using a new model of accounting for energies related to the dissociated configurations. This model relies on quantum mechanical calculations for total crystal energies of various other crystal structures, similar to DO$\\sb{22}$, which are present locally within the faulted region of the dissociated dislocations. A possible extrapolation to the case of $\\rm L1\\sb2$ compounds is also given.","Made available in DSpace on 2011-05-07T13:40:54Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9026350.pdf: 15842533 bytes, checksum: ef4574537ecb2545d9b816e30ca44b5c (MD5) Previous issue date: 1990","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:57:50Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:27:09-05:00 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","U of I Only"]},{"key":"dc:title","label":"Title","values":["Defect and deformation studies in transition metal trialuminide compounds"]}]}],"canonical_facts":{"dc:contributor":["Fraser, Hamish L."],"dc:creator":["Wheeler, Robert, IV"],"dc:date":["2011-05-07T13:40:54Z","10000-01-01","1990"],"dc:description":["Defect studies have been performed on the intermetallic compounds $\\rm Al\\sb3Ti$, $\\rm Al\\sb3V$ and $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$ which were deformed at elevated temperatures. Test materials were prepared via the rapid solidification route. TEM characterizations indicated that the microstructure of the asatomized Al-25at.%Ti alloy powder consisted of primary dendrites of the $\\rm Al\\sb3Ti$ phase (DO$\\sb{22}$ structure) and $\\alpha$-aluminum. The as-atomized Al-25at.%V alloy exhibited a microstructure composed of primary $\\rm Al\\sb8V\\sb5$ dendrites with interdendritic $\\rm Al\\sb3V$ (DO$\\sb{22}$) and $\\alpha$-aluminum. The Al-8at.%Ni-25at.% Ti alloy exhibited dendrites of $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$(L1$\\sb2$) and small $\\rm Al\\sb3Ni\\sb2$ particles.","The consolidated Al-25at.%Ti alloy contained $\\rm Al\\sb3Ti$ with numerous small particles. Three types of second phases were noted: TiAl particles, oxide streamers at prior particle boundaries; and small TiC particles within certain grains. In the consolidated Al-25at.%V powder, large $\\rm Al\\sb8V\\sb5$ particles were identified within a matrix of $\\rm Al\\sb3V$. The Al-8at.%Ni-25at.%Ti alloy contained $\\rm Al\\sb2NiTi$ particles (fcc, a$\\sb0$ = 11.94A) in a matrix of $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$.","Compression testing was carried out at 300$\\sp\\circ$C, 600$\\sp\\circ$C and 800$\\sp\\circ$C. The weak-beam darkfield technique was employed to determine the Burgers vector, slip plane and dissociation reactions of dislocations responsible for plastic deformation.","In $\\rm Al\\sb3Ti$, microtwins on the close packed $\\{112)$ planes formed by the repeated passage of 1/6 $<$ 111) partial dislocations on successive $\\{112)$ planes were identified. Partial dislocations with b = 1/2 $<$ 110) which bound APB's on the (001) plane were also characterized at 300$\\sp\\circ$C and 600$\\sp\\circ$C. Dislocations with b = $<$100) were found to glide on (001) and shown to climb at the higher temperatures ($\\geq$600$\\sp\\circ$C). $\\rm Al\\sb3V$ appears to deform by glide of b = $<$110) dislocation son the $\\{112)$ planes. At 800$\\sp\\circ$C, again climbing $<$100) dislocations were found. In $\\rm Al\\sb{67}Ni\\sb8Ti\\sb{25}$, dislocation glide of the type $\\langle 110\\rangle\\{111\\}$ was identified. At 300$\\sp\\circ$C, the dislocations were undissociated, while at 600$\\sp\\circ$C and 800$\\sp\\circ$C, considerable APB-type dissociation on the $\\{001\\}$ planes was noted.","Defect structures in the two DO$\\sb{22}$ compounds have been explained using a new model of accounting for energies related to the dissociated configurations. This model relies on quantum mechanical calculations for total crystal energies of various other crystal structures, similar to DO$\\sb{22}$, which are present locally within the faulted region of the dissociated dislocations. A possible extrapolation to the case of $\\rm L1\\sb2$ compounds is also given.","Made available in DSpace on 2011-05-07T13:40:54Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9026350.pdf: 15842533 bytes, checksum: ef4574537ecb2545d9b816e30ca44b5c (MD5) Previous issue date: 1990","Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T14:57:50Z Item is restricted indefinitely.","Restriction data tranferred 2014-07-01T11:27:09-05:00 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","U of I Only"],"dc:identifier":["AAI9026350","(UMI)AAI9026350","http://hdl.handle.net/2142/22470"],"dc:language":["eng"],"dc:rights":["Copyright 1990 Wheeler, Robert, IV"],"dc:subject":["Engineering, Metallurgy","Engineering, Materials Science"],"dc:title":["Defect and deformation studies in transition metal trialuminide compounds"],"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":"2026-07-22T22:25:20Z"}