The 9th International Conference on Multiscale Materials Modeling

Presentation information

Symposium

L. Structure, Statistics and Mechanics in Crystal Dislocation Plasticity

[SY-L3] Symposium L-3

Tue. Oct 30, 2018 9:45 AM - 11:00 AM Room8

Chairs: Peter M Derlet(Paul Scherrer Institut, Switzerland), Cynthia Reichhardt(Los Alamos National Laboratory, United States of America)

[SY-L3] Intermittent micro-plasticity and its relation to dislocation structure - a linear stability analysis.

Invited

Peter M Derlet1, Gábor Péterffy2, Péter Dusán Ispánovity2 (1.Paul Scherrer Institut, Switzerland, 2.Department of Materials Physics, Eötvös University, Hungary)

The relationship between dislocation network stucture and plasticity is studied via a linear stability analysis of the evolving dislocation configuration. This is done for a simplified one dimensional model of interacting dislocation pile-ups, which exhibits a mean-field depinning transition at yield, and for a two dimensional dislocation dynamics model always in a state of criticality that is well described by a jamming transition. We find that the obtained eigen-modes prior to a plastic event play an important role in characterizing the discrete micro-plastic regime of simulation, reflecting the degree of criticality the system is in, the nature of how a plastic event occurs and its eventual evolution into an avalanche.