{"id":{"repo_id":"vt","oai_identifier":"oai:vtechworks.lib.vt.edu:10919/36650"},"canonical_url":"https://search.dev.ndltd.org/etd/vt/oai:vtechworks.lib.vt.edu:10919/36650","repository":{"repo_id":"vt","name":"Virginia Tech","base_url":"https://vtechworks.lib.vt.edu/oai/request"},"display":{"title":"Finite Element Analysis of Adiabatic Shear Bands in Impact and Penetration Problems","abstract":"We study axisymmetric deformations of depleted uranium (DU) and tungsten heavy alloy (WHA) rods impacting at normal incidence both a rigid, planar target and a thick, deformable steel target. Each deformable material is modeled as elastic thermoviscoplastic; the flow stress increases with an increase in the effective plastic strain and effective plastic strain-rate but decreases with a rise in the temperature. An objective of this work is to ascertain when and where a shear band, defined as a narrow region of rapid, intense plastic deformation, forms in each material subject to impact loading. The Taylor impact simulations show that shear bands form earlier in WHA than in DU for the material parameters used. In the penetration simulations, shear bands form continuously in the ejecta of the DU penetrator while only one shear band occurs in the WHA ejecta followed by more uniform deformations. Note: In order to view the computer animations referenced in this thesis, one must have a QuickTime movie player and download the files named Ujce.mov Uz2e.mov Uz3e.mov Wjce.mov Wz2e.mov and Wz3e.mov from the same directory the \"pdf\" file resides in.","abstract_html":"We study axisymmetric deformations of depleted uranium (DU) and tungsten heavy alloy (WHA) rods impacting at normal incidence both a rigid, planar target and a thick, deformable steel target. Each deformable material is modeled as elastic thermoviscoplastic; the flow stress increases with an increase in the effective plastic strain and effective plastic strain-rate but decreases with a rise in the temperature. An objective of this work is to ascertain when and where a shear band, defined as a narrow region of rapid, intense plastic deformation, forms in each material subject to impact loading. The Taylor impact simulations show that shear bands form earlier in WHA than in DU for the material parameters used. In the penetration simulations, shear bands form continuously in the ejecta of the DU penetrator while only one shear band occurs in the WHA ejecta followed by more uniform deformations. Note: In order to view the computer animations referenced in this thesis, one must have a QuickTime movie player and download the files named Ujce.mov Uz2e.mov Uz3e.mov Wjce.mov Wz2e.mov and Wz3e.mov from the same directory the "pdf" file resides in.","abstract_has_math":false,"creators":["Stevens, John Boyet"],"institution":"Virginia Tech","degree_name":"Master of Science","degree_level":"masters","degree_discipline":"Engineering Science and Mechanics","degree_department":"Engineering Science and Mechanics","school":null,"contributors":[],"advisors":[],"committee_chairs":["Batra, Romesh C.","Kriz, Ronald D."],"committee_members":["Kohler, Werner E."],"year":1996,"date_issued":"1996-11-22","date_published":"1996-11-22","updated_at":"2026-07-22T22:20:03Z","subjects":["Taylor impact test","ballistic","Simulation","localization"],"languages":[],"rights":["In Copyright"],"rights_urls":["http://rightsstatements.org/vocab/InC/1.0/"],"identifier_entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-3753128097370"],"render_values":[{"text":"etd-3753128097370","href":null,"code":true}]}]},"links":{"outbound_url":"http://hdl.handle.net/10919/36650","outbound_label":"Handle","outbound_source":"dc:identifier.uri"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor.committeechair","label":"Committee Chair","values":["Batra, Romesh C.","Kriz, Ronald D."]},{"key":"dc:contributor.committeemember","label":"Committee Member","values":["Kohler, Werner E."]},{"key":"dc:contributor.department","label":"Department","values":["Engineering Science and Mechanics"]},{"key":"dc:creator","label":"Author","values":["Stevens, John Boyet"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date.accessioned","label":"Dc Date Accessioned","values":["2014-03-14T20:51:23Z"]},{"key":"dc:date.available","label":"Dc Date Available","values":["2014-03-14T20:51:23Z","1996-11-22"]},{"key":"dc:date.issued","label":"Date","values":["1996-11-22"]},{"key":"dc:publisher","label":"Institution","values":["Virginia Tech"]},{"key":"dc:type","label":"Dc Type","values":["Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Engineering Science and Mechanics"]},{"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":["Virginia Polytechnic Institute and State University"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Taylor impact test","ballistic","Simulation","localization"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:rights","label":"Dc Rights","values":["In Copyright"]},{"key":"dc:rights.uri","label":"Rights URI","values":["http://rightsstatements.org/vocab/InC/1.0/"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier.other","label":"Dc Identifier Other","values":["etd-3753128097370"]},{"key":"dc:identifier.uri","label":"Identifier URI","values":["http://hdl.handle.net/10919/36650"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description.abstract","label":"Abstract","values":["We study axisymmetric deformations of depleted uranium (DU) and tungsten heavy alloy (WHA) rods impacting at normal incidence both a rigid, planar target and a thick, deformable steel target. Each deformable material is modeled as elastic thermoviscoplastic; the flow stress increases with an increase in the effective plastic strain and effective plastic strain-rate but decreases with a rise in the temperature. An objective of this work is to ascertain when and where a shear band, defined as a narrow region of rapid, intense plastic deformation, forms in each material subject to impact loading. The Taylor impact simulations show that shear bands form earlier in WHA than in DU for the material parameters used. In the penetration simulations, shear bands form continuously in the ejecta of the DU penetrator while only one shear band occurs in the WHA ejecta followed by more uniform deformations. Note: In order to view the computer animations referenced in this thesis, one must have a QuickTime movie player and download the files named Ujce.mov Uz2e.mov Uz3e.mov Wjce.mov Wz2e.mov and Wz3e.mov from the same directory the \"pdf\" file resides in."]},{"key":"dc:description.degree","label":"Dc Description Degree","values":["Master of Science"]},{"key":"dc:title","label":"Title","values":["Finite Element Analysis of Adiabatic Shear Bands in Impact and Penetration Problems"]}]}],"canonical_facts":{"dc:contributor.committeechair":["Batra, Romesh C.","Kriz, Ronald D."],"dc:contributor.committeemember":["Kohler, Werner E."],"dc:contributor.department":["Engineering Science and Mechanics"],"dc:creator":["Stevens, John Boyet"],"dc:date.accessioned":["2014-03-14T20:51:23Z"],"dc:date.available":["2014-03-14T20:51:23Z","1996-11-22"],"dc:date.issued":["1996-11-22"],"dc:description.abstract":["We study axisymmetric deformations of depleted uranium (DU) and tungsten heavy alloy (WHA) rods impacting at normal incidence both a rigid, planar target and a thick, deformable steel target. Each deformable material is modeled as elastic thermoviscoplastic; the flow stress increases with an increase in the effective plastic strain and effective plastic strain-rate but decreases with a rise in the temperature. An objective of this work is to ascertain when and where a shear band, defined as a narrow region of rapid, intense plastic deformation, forms in each material subject to impact loading. The Taylor impact simulations show that shear bands form earlier in WHA than in DU for the material parameters used. In the penetration simulations, shear bands form continuously in the ejecta of the DU penetrator while only one shear band occurs in the WHA ejecta followed by more uniform deformations. Note: In order to view the computer animations referenced in this thesis, one must have a QuickTime movie player and download the files named Ujce.mov Uz2e.mov Uz3e.mov Wjce.mov Wz2e.mov and Wz3e.mov from the same directory the \"pdf\" file resides in."],"dc:description.degree":["Master of Science"],"dc:identifier.other":["etd-3753128097370"],"dc:identifier.uri":["http://hdl.handle.net/10919/36650"],"dc:publisher":["Virginia Tech"],"dc:rights":["In Copyright"],"dc:rights.uri":["http://rightsstatements.org/vocab/InC/1.0/"],"dc:subject":["Taylor impact test","ballistic","Simulation","localization"],"dc:title":["Finite Element Analysis of Adiabatic Shear Bands in Impact and Penetration Problems"],"dc:type":["Thesis"],"thesis:degree_discipline":["Engineering Science and Mechanics"],"thesis:degree_level":["masters"],"thesis:degree_name":["Master of Science"],"thesis:institution_name":["Virginia Polytechnic Institute and State University"]},"updated_at":"2026-07-22T22:20:03Z"}