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Shawki, Tarek G. Sherif, Raed A. 2011-05-07T14:16:51Z 2011-05-07T14:16:51Z 10000-01-01 1989 The mechanics of adiabatic shear bands are investigated through the study of a one-dimensional simple shearing model. The materials considered are assumed to exhibit strain rate hardening, thermal softening, and strain hardening or softening. The mechanism leading to shear band formation is assumed to be a thermo-mechanical mechanism. First, we identify the different stages associated with the localization of plastic flow. The limits of validity of the thermo-mechanical mechanism are then discussed. We investigate the existence and uniqueness of a homogeneous, spatially independent solution to the problem. Accordingly, we present a distinction between the notions of shear instability and shear localization. Necessary and sufficient conditions for shear instability are derived. We investigate the necessary and sufficient conditions for the homogeneous deformation to localize through the use of a linear stability theory. The analysis is supported by numerical solutions to the nonlinear system of governing equations. We then investigate the behavior of the field variables at the late stages of deformation. We present an exact steady state formulation for the nonlinear problem. Exact and asymptotic solutions are obtained for the steady state problem. Made available in DSpace on 2011-05-07T14:16:51Z (GMT). No. of bitstreams: 2 license.txt: 4922 bytes, checksum: 910b249b4beec47e7ab768910c8f966f (MD5) 9011018.pdf: 7431560 bytes, checksum: 8668d5ed0e6ebc598a3a4a5f6fce2a0b (MD5) Previous issue date: 1989 Item marked as restricted to the 'UIUC Users [automated]' Group (id=2) by Howard Ding (hding2@illinois.edu) on 2011-05-07T15:04:57Z Item is restricted indefinitely. Restriction data tranferred 2014-07-01T11:31:04-05:00 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 AAI9011018 (UMI)AAI9011018 http://hdl.handle.net/2142/23509 eng Copyright 1989 Sherif, Raed A. Applied Mechanics The mechanics of shear-band formation in thermal viscoplastic materials at high rates of loading text Applied Mechanics Applied Mechanics University of Illinois at Urbana-Champaign Dissertation Ph.D.