University of Minnesota
Aerospace Engineering and Mechanics
Spring 2001 Seminar Series
A gradient theory of single-crystal plasticity that accounts for
geometrically necessary dislocations
This talk will discuss the kinematics of of geometrically necessary
dislocations (GNDs) in finite plasticity and will develop a gradient theory
that accounts for GNDs within a thermomechanical framework. The theory is based
on classical macroforces; microforces for each slip system consistent with a
microforce balance; a mechanical version of the second law that includes, via
the microforces, work performed during slip; a rate-dependent constitutive
theory that includes dependences on a tensorial measure of geometrically
necessary dislocations. The microforce balances are equivalent to nonlocal
(pde) yield conditions for the individual slip systems. To make contact with
classical dislocation theory, the microstresses are shown to represent
counterparts of the Peach-Koehler force on a single dislocation.
Friday, May 4, 2001
Refreshments served after the seminar in
227 Akerman Hall.
Disability accomodations provided upon request.
Contact Kristal Belisle, Senior