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Propagating solitary waves along a rapidly moving crack front
E Sharon1, G Cohen, J Fineberg
1The Racah Institute of Physics, The Hebrew University of Jerusalem, Givat Ram, Israel.
Nature
|March 10, 2001
Summary
Newly discovered
Area of Science:
- Fracture mechanics
- Materials science
- Solid mechanics
Background:
- Cracks in brittle materials are often simplified as 1D objects in 2D materials.
- Real 3D materials exhibit planar crack surfaces with singular fronts.
- Dynamics and morphology of crack fronts interacting with inhomogeneities are not understood.
Purpose of the Study:
- Investigate the dynamics of crack fronts in 3D brittle materials.
- Understand the role of material inhomogeneities on crack front behavior.
- Explain the formation of fracture surface morphology.
Main Methods:
- Simulations of crack front dynamics in 3D brittle materials.
- Analysis of wave propagation along crack fronts.
- Examination of crack front interaction with asperities.
Main Results:
- Perturbations create long-lived, localized waves ('front waves') propagating along crack fronts.
- Front waves propagate at approximately Rayleigh wave speed.
- Counter-propagating front waves maintain shape and amplitude, creating surface traces.
Conclusions:
- Front waves are intrinsically 3D phenomena, absent in 2D fracture theories.
- Front waves provide cracks with inertia and dissipation.
- They may explain crack coherence during interactions with asperities.
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