Type of Document Master's Thesis Author Stevens, John Boyet URN etd-3753128097370 Title Finite Element Analysis of Adiabatic Shear Bands in Impact and Penetration Problems Degree Master of Science Department Engineering Science and Mechanics Advisory Committee
Advisor Name Title Kohler, Werner E. Batra, Romesh C. Committee Chair Kriz, Ronald D. Committee Co-Chair Keywords
- taylor impact test
Date of Defense 1996-11-22 Availability unrestricted AbstractWe 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.
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Filename Size Approximate Download Time (Hours:Minutes:Seconds)
28.8 Modem 56K Modem ISDN (64 Kb) ISDN (128 Kb) Higher-speed Access stevens.pdf 2.88 Mb 00:13:21 00:06:51 00:06:00 00:03:00 00:00:15 Ujce.mov 3.93 Mb 00:18:11 00:09:21 00:08:11 00:04:05 00:00:20 Uz2e.mov 3.87 Mb 00:17:54 00:09:12 00:08:03 00:04:01 00:00:20 Uz3e.mov 4.19 Mb 00:19:24 00:09:58 00:08:44 00:04:22 00:00:22 Wjce.mov 3.97 Mb 00:18:22 00:09:27 00:08:16 00:04:08 00:00:21 Wz2e.mov 2.96 Mb 00:13:41 00:07:02 00:06:09 00:03:04 00:00:15 Wz3e.mov 1.48 Mb 00:06:52 00:03:32 00:03:05 00:01:32 00:00:07
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