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Updated: Jun 1, 2026
09:12
A Method for Studying the Temperature Dependence of Dynamic Fracture and Fragmentation
Published on: June 28, 2015
Brittle fracture in viscoelastic materials as a pattern-formation process
M Fleck1, D Pilipenko, R Spatschek
1Lehrstuhl für Material und Prozesssimulation, Universität Bayreuth, Germany. michael.fleck@uni-bayreuth.de
Summary
This study presents a continuum model for crack propagation in brittle viscoelastic materials, understanding fracture as pattern formation. Inertial and viscous effects are crucial for self-selected crack velocity and shape.
Area of Science:
- Continuum mechanics
- Materials science
- Fracture mechanics
Background:
- Fracture is modeled as an elastically induced nonequilibrium interfacial pattern formation.
- Crack propagation involves determining the time-dependent shape of the crack surface.
- Crack motion is governed by linear nonequilibrium transport equations.
Purpose of the Study:
- To present and discuss a continuum model for crack propagation in brittle viscoelastic materials.
- To identify mechanisms for self-selected crack velocity and shape.
- To numerically explore steady-state crack propagation under various conditions.
Main Methods:
- Utilizing linear nonequilibrium transport equations for crack motion.
- Employing scaling arguments to demonstrate the existence of steady-state solutions.
- Solving free boundary problems with phase field methods and sharp interface approaches.
Main Results:
- Steady-state crack propagation requires elastodynamic or viscoelastic effects; static elasticity is insufficient.
- Inertial effects and viscous damping act as crack tip selection mechanisms.
- Numerical simulations cover viscoelastic, inertia, and intermediate regimes for crack propagation.
Conclusions:
- The model provides a framework for understanding brittle fracture as a pattern formation process.
- Inertial and viscous effects are essential for stable crack propagation and shape selection.
- The study validates the use of phase field and sharp interface methods for fracture analysis.
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