Evolution of displacements and strains in sheared amorphous solids

Abstract

The local deformation of two-dimensional Lennard-Jones glasses under imposed shear strain is studied via computer simulations. Both the mean squared displacement and mean squared strain rise linearly with the length of the strain interval ∆γ over which they are measured. However, the increase in displacement does not represent single-particle diffusion. There are long-range spatial correlations in displacement associated with slip lines with an amplitude of order the particle size. Strong dependence on system size is also observed. The probability distributions of displacement and strain are very different. For small ∆γ the distribution of displacement has a plateau followed by an exponential tail. The distribution becomes Gaussian as ∆γ increases to about .03. The strain distributions consist of sharp central peaks associated with elastic regions, and long exponential tails associated with plastic regions. The latter persist to the largest ∆γ studied.

Mechanical Properties of Metallic Glasses

“…On the other hand the LJ glass shows almost continuous softening with a very small critical strain (ε red ~ 2 × 10 −5 << ε 1 ). Thus in the LJ glass the two softening processes are not distinct and bond-cutting is not a discrete jump process, in agreement with other reports on this system [17,18].…”

“…Thus for the system with the mJ potential the two mechanisms of softening contribute by comparable amounts. Then, why some authors [6,17,18] do not observe the second, bond reorientational effect? To answer this question we repeated the same simulation for the Lennard-Jones (LJ) glass and the glass with the Dzugutov (Dz) potential [26].…”

“…Instead numerical solution, including the finite element analysis, is usually sought in obtaining the answer. This elastic heterogeneity has been considered to be the reason for softening of shear modulus, G, by Weaire et al [6], and in a number of simulation results [17,18].…”

From depinning transition to plastic yielding of amorphous media: A soft-modes perspective

“…Recently summarized in Ref. [35], most features of the associated scaling phenomenology predicted by depinning-like models of amorphous plasticity have been observed numerically [37][38][39][40] and experimentally [1,2].…”

Coarse-graining microscopic strains in a harmonic, two-dimensional solid: Elasticity, nonlocal susceptibilities, and nonaffine noise

“…What is the effect of these configurations on elasticity and how do they influence mechanical behavior? Recently, there has been significant progress in the study of non-affineness in solid plasticity -especially in the context of rheological properties of amorphous materials and granular solids which show jamming behavior [12,13,14]. Localized non-affine regions consisting of particles capable of large reorientations have been shown to be involved in relaxation processes in these systems.…”