How glass breaks -- Damage explains the difference between surface and fracture energies in amorphous silica

Gergely Molnár; Etienne Barthel

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arXiv · 2412.11817

How glass breaks -- Damage explains the difference between surface and fracture energies in amorphous silica

Gergely Molnár·Etienne Barthel

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Abstract

The difference between free surface energy and fracture toughness in amorphous silica is studied via multi-scale simulations. We combine the homogenization of a molecular dynamics fracture model with a phase-field approach to track and quantify the various energy contributions. We clearly separate free surface energy localized as potential energy on the surface and damage diffusion over a 16-23 A range around the crack path. The plastic contribution is negligible. These findings, which clarify brittle fracture mechanisms in amorphous materials, align with toughness measurements in silica.

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Gergely Molnár, Etienne Barthel. 2024-12-16. How glass breaks -- Damage explains the difference between surface and fracture energies in amorphous silica. https://arxiv.org/abs/2412.11817

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