Optimization and plasticity in disordered media

Abstract

We study the plastic yielding of disordered media using the perfectly plastic random fuse model. The yield surfaces are shown to be different from those obtained minimizing the sum of the local yield thresholds, i.e. the so-called minimum 'energy' surfaces. As a result, the global yield stress is lower than expected from naive optimization and the difference persists as the sample size increases. At variance with minimum energy surfaces, height-height fluctuations of yield surfaces exhibit multiscaling. We provide a theoretical argument that explains how this behavior arises from the very different nature of the optimization problem in both cases.

Accepted for publication in Physical Review Letters

References in corpus (5)

• Statistical Models of Fracture
• Shear-transformation-zone theory of plastic deformation near the glass transition
• Plastic response of a 2D amorphous solid to quasi-static shear : I - Transverse particle diffusion and phenomenology of dissipative events
• Size effects in statistical fracture
• Probing the tails of the ground state energy distribution for the directed polymer in a random medium of dimension $d=1,2,3$ via a Monte-Carlo procedure in the disorder

Cited by in corpus (2)

• Elasto-plastic description of brittle failure in amorphous materials
• From Brittle to Ductile Fracture in Disordered Materials