Self-diffusion in plastic flow of amorphous solids

Abstract

We report on a particle-based numerical study of sheared amorphous solids in the dense slow flow regime. In this framework, deformation and flow are accompanied by critical fluctuation patterns associated with the macroscopic plastic response and single particle kinematics. The former is commonly attributed to the collective slip patterns that relax internal stresses within the bulk material and give rise to an effective mechanical noise governing the latter particle-level process. In this work, the avalanche-type dynamics between plastic events is shown to have a strong relevance on the self-diffusion of tracer particles in the Fickian regime. As a consequence, strong size effects emerge in the effective diffusion coefficient that is rationalized in terms of avalanche size distributions and the relevant temporal occurrence.

References in corpus (15)

• Scaling description of the yielding transition in soft amorphous solids at zero temperature
• Elastic consequences of a single plastic event : a step towards the microscopic modeling of the flow of yield stress fluids
• Local Stress Relaxation and Shear-banding in a Dry Foam under Shear
• Driving rate dependence of avalanche statistics and shapes at the yielding transition
• Avalanches in Strained Amorphous Solids: Does Inertia Destroy Critical Behavior?
• On the density of shear transformation zones in amorphous solids
• Shear bands as manifestation of a criticality in yielding amorphous solids
• Connecting diffusion and dynamical heterogeneities in actively deformed amorphous systems
• Plastic response of a 2D amorphous solid to quasi-static shear : I - Transverse particle diffusion and phenomenology of dissipative events
• Statistical Physics of Elasto-Plastic Steady States in Amorphous Solids: Finite Temperatures and Strain Rates
• On the relevance of disorder in athermal amorphous materials under shear
• Evolution of displacements and strains in sheared amorphous solids
• Robustness of avalanche dynamics in sheared amorphous solids as probed by transverse diffusion
• Super-diffusion around the rigidity transition: Levy and the Lilliputians
• Diffusion in mesoscopic lattice models of amorphous plasticity