Evolution of the pore size distribution in sheared binary glasses

TL;DR

This study uses molecular dynamics simulations to explore how shear deformation affects the pore structure and mechanical properties of binary glasses, revealing pore coalescence and distribution broadening at higher strains.

Contribution

It provides new insights into the evolution of pore size distribution and mechanical response of binary glasses under shear deformation.

Findings

Pore size distribution broadens with increasing strain.

Shear modulus depends strongly on porosity.

Pores tend to coalesce at higher strains.

Abstract

Molecular dynamics simulations are carried out to investigate mechanical properties and porous structure of binary glasses subjected to steady shear. The model vitreous systems were prepared via thermal quench at constant volume to a temperature well below the glass transition. The quiescent samples are characterized by a relatively narrow pore size distribution whose mean size is larger at lower glass densities. We find that in the linear regime of deformation, the shear modulus is a strong function of porosity, and the individual pores become slightly stretched while their structural topology remains unaffected. By contrast, with further increasing strain, the shear stress saturates to a density-dependent plateau value, which is accompanied by pore coalescence and a gradual development of a broader pore size distribution with a discrete set of peaks at large length scales.