Branching Instabilities in Rapid Fracture: Dynamics and Geometry

TL;DR

This paper presents a theoretical model for crack branching in 2D fracture, predicting when and how cracks branch and their geometries, aligning well with experimental observations.

Contribution

It introduces a novel crack tip dynamics model based on stress intensity factors, linking static and dynamic aspects for predicting branching behavior.

Findings

Model accurately predicts crack branching conditions.

Good agreement with experimental data.

Provides insights into crack geometry development.

Abstract

We propose a theoretical model for branching instabilities in 2-dimensional fracture, offering predictions for when crack branching occurs, how multiple cracks develop, and what is the geometry of multiple branches. The model is based on equations of motion for crack tips which depend only on the time dependent stress intensity factors. The latter are obtained by invoking an approximate relation between static and dynamic stress intensity factors, together with an essentially exact calculation of the static ones. The results of this model are in good agreement with a sizeable quantity of experimental data.