Plastic deformation of a model glass induced by a local shear transformation

Abstract

The effect of a local shear transformation on plastic deformation of a three-dimensional amorphous solid is studied using molecular dynamics simulations. We consider a spherical inclusion, which is gradually transformed into an ellipsoid of the same volume and then converted back into the sphere. It is shown that at sufficiently large strain amplitudes, the deformation of the material involves localized plastic events that are identified based on the relative displacement of atoms before and after the shear transformation. We find that the density profiles of cage jumps decay away from the inclusion, which correlates well with the radial dependence of the local deformation of the material. At the same strain amplitude, the plastic deformation becomes more pronounced in the cases of weakly damped dynamics or large time scales of the shear transformation. We show that the density profiles can be characterized by the universal function of the radial distance multiplied by a dimensionless factor that depends on the friction coefficient and the time scale of the shear event.

Eshelby inclusions in granular matter: Theory and simulations

“…(1), at the beginning of Eshelby's calcution. The alternative of imposing displacements [30,31] corresponds to imposingũ i inside the inclusion. But Eshelby's calculation does not begin withũ i , but rather with σ * (or e * if the elastic moduli are known).…”

Nonaffine rearrangements of atoms in deformed and quiescent binary glasses

“…In turn, a local reversible shear transformation in a quiescent glass can trigger irreversible cage jumps whose density is large when the system dynamics is weakly damped or the shear transformation is slow [21,22]. More recently, a sharp transition from affine to nonaffine displacements of particles was identified in colloidal glasses under variable-amplitude oscillatory shear [6,7].…”

Collective nonaffine displacements in amorphous materials during large-amplitude oscillatory shear

“…Furthermore, during cyclic shear near the yield strain, a cluster of atoms with large reversible nonaffine displacements induces a long-range, time-dependent elastic field that in turn might trigger secondary structural rearrangements. This situation was considered separately in recent studies [31,32], where it was found that a local reversible shear transformation in a quiescent system induces irreversible cage jumps, and their density is larger in the cases of weaker damping or slower shear transformation.…”