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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. A nonlinear multiple slip theory in continuum dislocation dynamics
 ElAzab, A. ; Florida State University, Department of Scientific Computing: MMM 2008, Fourth International Conference Multiscale Materials Modeling : October 2731, 2008, Tallahassee, Florida, USA Tallahassee, Fla., 2008 ISBN: 9780615247816 S.115118 
 International Conference on Multiscale Materials Modeling (MMM) <4, 2008, Tallahassee/Fla.> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer IWM () 
 nonlinear; dislocation 
Abstract
Crystal plasticity is the result of the motion and complex and effectively nonlinear interactions of dislocations. The collective behaviour of dislocations plays a prominent role both for the evolution of dislocation structures and as origin of strain hardening. There is, however, still a major gap between microscopic and mesoscopic simulations and continuum crystal plasticity models. Only recently a higher dimensional dislocation density tensor was defined which overcomes some drawbacks of earlier dislocation density measures. The evolution equation for this tensor can be considered as a continuum version of dislocation dynamics. We use this tensor to develop a nonlinear theory of multiple slip deformation. Starting from the rate of dislocation cutting events per volume, we deduce the m ean area swept by dislocations between cutting events and the closely related mean free segment length. If the mean dislocation velocity depends on the mean free segment length this leads to an important nonlinearity which we illustrate by means of a simple example.