Title page for ETD etd-3753128097370

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
Romesh C. Batra	Committee Chair
Ronald D. Kriz	Committee Co-Chair
Werner Kohler	none

Keywords

taylor impact test
ballistic
simulation
localization

Date of Defense

1996-11-22

Availability

unrestricted

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.

Files

Filename		Size	Approximate Download Time (Hours:Minutes:Seconds)
Filename		Size	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