Evaluation of the Disorder Temperature and Free-Volume Formalisms via Simulations of Shear Banding in Amorphous Solids

Molecular dynamics simulations of shear band development over 1000% strain in simple shear are used to test whether the local plastic strain rate is proportional to exp(-1/chi), where chi is a dimensionless quantity related to the disorder temperature or free volume that characterizes the structural state of the glass. Scaling is observed under the assumption that chi is linearly related to the local potential energy per atom. We calculate the potential energy per atom corresponding to absolute zero disorder temperature and the energy needed to create a shear transformation zone.