Shear yielding of amorphous glassy solids: Effect of temperature and strain rate

Publication Type
Journal Article
Year of Publication
2003
Authors
Rottler, Jörg
Robbins, Mark O.
Name of Publication
Physical Review E
Volume
68
Pagination
011507
Date Published
jul
Abstract

We study shear yielding and steady state flow of glassy materials with molecular dynamics simulations of two standard models: amorphous polymers and bidisperse {Lennard-Jones} glasses. For a fixed strain rate, the maximum shear yield stress and the steady state flow stress in simple shear both drop linearly with increasing temperature. The dependence on strain rate can be described by either a logarithm or a power law added to a constant. In marked contrast to predictions of traditional thermal activation models, the rate dependence is nearly independent of temperature. The relation to more recent models of plastic deformation and glassy rheology is discussed, and the dynamics of particles and stress in small regions is examined in light of these findings.