Universality in the fracture of silica glass

TL;DR

This paper investigates the universal statistical properties of fracture avalanches in silica glass at the microscale, revealing power-law behaviors and universality class connections through molecular mechanics simulations.

Contribution

It introduces a new method for analyzing fracture avalanches and demonstrates their universal scaling laws, linking nanoscale silica fracture to depinning models.

Findings

Avalanche size distributions follow universal power laws.

Nanoscale silica fracture belongs to the depinning universality class.

Distinct scaling behaviors are observed for small and large avalanches.

Abstract

The presence of universality of avalanches characterizing the inelastic response of disordered materials has the potential to bridge the gap from micro- to macroscale. In this study, we explore the statistics and the scaling behavior of avalanches in the fracture of silica glass on the microscale using molecular mechanics. We introduce a robust method for capturing and quantifying the avalanches, allowing us to perform rigorous statistical analysis, revealing universal power laws associated with critical phenomena. The computed exponents suggest that nanoscale fracture of silica belongs to the same universality class as depinning models. Additionally, the influence of an initial crack is explored, observing deviations from mean-field predictions while maintaining criticality. Furthermore, we investigate the strain-dependent probability density function (PDF), its cutoff function, and the interrelation between the critical exponents. Finally, we unveil distinct scaling behavior for small and large avalanches of the crack growth, shedding light on the underlying fracture mechanisms in silica glass.