In the preceding paper, we developed an athermal shear-transformation-zone(STZ) theory of amorphous plasticity. Here we use this theory in an analysis ofnumerical simulations of plasticity in amorphous silicon by Demkowicz and Argon(DA). In addition to bulk mechanical properties, those authors observedinternal features of their deforming system that challenge our theory inimportant ways. We propose a quasithermodynamic interpretation of theirobservations in which the effective disorder temperature, generated bymechanical deformation well below the glass temperature, governs the behaviorof other state variables that fall in and out of equilibrium with it. Ouranalysis points to a limitation of either the step-strain procedure used by DAin their simulations, or the STZ theory in its ability to describe rapidtransients in stress-strain curves, or perhaps to both. Once we allow for thislimitation, we are able to bring our theoretical predictions into accurateagreement with the simulations.
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