Fronts Propagation at the Onset of Plastic Yielding
arXiv:0707.4573 · doi:10.1103/PhysRevE.78.026119
Abstract
The existence of a finite threshold, the yield stress, for the onset of plastic yielding is a universal feature of plasticity. This jamming-unjamming transition is naturally accounted for by the dynamics of a bistable internal state field. We show, within the athermal Shear Transformation Zones (STZ) theory of amorphous plasticity, that the transition is accompanied by the propagation of plastic fronts. We further show that the mean-field theory cannot select the velocity of these fronts and go beyond the mean-field description to include fluctuations and correlations effects, resulting in new nonlocal terms in the equations. Finally, we demonstrate that the new terms, with an associated intrinsic lengthscale, provide a velocity selection mechanism for the plastic fronts.
6 pages, 1 figure; reorganized paper, friction part omitted
References in corpus (17)
- Dynamics of Viscoplastic Deformation in Amorphous Solids
- Front propagation into unstable states
- Amorphous Systems in Athermal, Quasistatic Shear
- Strain localization and percolation of stable structure in amorphous solids
- Subextensive Scaling in the Athermal, Quasistatic Limit of Amorphous Matter in Plastic Shear Flow
- Shear-transformation-zone theory of plastic deformation near the glass transition
- Strain localization in a shear transformation zone model for amorphous solids
- An extremal model for amorphous media plasticity
- Evaluation of the "disorder temperature" and "free volume" formalisms via simulations of shear banding in amorphous solids
- Athermal Shear-Transformation-Zone Theory of Amorphous Plastic Deformation I: Basic Principles
- Reversible plasticity in amorphous materials
- Steady-state, effective-temperature dynamics in a glassy material
- Athermal Shear-Transformation-Zone Theory of Amorphous Plastic Deformation II: Analysis of Simulated Amorphous Silicon
- Direct Identification of the Glass Transition: Growing Length Scale and the Onset of Plasticity
- Dynamics of Large-Scale Plastic Deformation and the Necking Instability in Amorphous Solids
- Dynamic Failure in Amorphous Solids via a Cavitation Instability
- Effective Temperature Dynamics in an Athermal Amorphous Plasticity Theory