The yielding transition in periodically sheared binary glasses at finite temperature

TL;DR

This study uses molecular dynamics simulations to explore how binary glasses respond to periodic shear at finite temperatures, revealing the transition from elastic to plastic behavior and shear band formation.

Contribution

It uncovers the dynamic yielding transition in binary glasses under periodic shear, highlighting the evolution of mechanical properties and structural rearrangements.

Findings

Potential energy decreases below yield, indicating energy minimization.

Below yield, storage modulus dominates and clusters of nonaffine atoms decay.

Above yield, loss modulus increases and shear bands form.

Abstract

Non-equilibrium molecular dynamics simulations are performed to investigate the dynamic behavior of three-dimensional binary glasses prepared via an instantaneous quench across the glass transition. We found that with increasing strain amplitude up to a critical value, the potential energy approaches lower minima in steady state, whereas the amplitude of shear stress oscillations becomes larger. Below the yielding transition, the storage modulus dominates the mechanical response, and the gradual decay of the potential energy over consecutive cycles is accompanied by reduction in size of transient clusters of atoms with large nonaffine displacements. In contrast, above the yield strain, the loss modulus increases and the system settles at a higher level of potential energy due to formation of a system-spanning shear band after a number of transient cycles.