Topological defects govern crack front motion and facet formation on broken surfaces

Kolvin, Itamar; Cohen, Gil; Fineberg, Jay

doi:10.1038/nmat5008

Cited by 42 publications

(42 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For example, numerous studies have shown that vigorous movements (e.g., >30% uniaxial strain) can disable the Pt film-based wearable electronics 1,14 . Although past studies have investigated the process of crack initiation and penetration 6,10,15–17 , manipulation of crack retardation to impart the metal film-based wearable electronics with ultrastretchability as well as high sensitivity has not yet been described.…”

Section: Introductionmentioning

confidence: 99%

Micro-/nano-voids guided two-stage film cracking on bioinspired assemblies for high-performance electronics

et al. 2019

View full text Add to dashboard Cite

Current metal film-based electronics, while sensitive to external stretching, typically fail via uncontrolled cracking under a relatively small strain (~30%), which restricts their practical applications. To address this, here we report a design approach inspired by the stereocilia bundles of a cochlea that uses a hierarchical assembly of interfacial nanowires to retard penetrating cracking. This structured surface outperforms its flat counterparts in stretchability (130% versus 30% tolerable strain) and maintains high sensitivity (minimum detection of 0.005% strain) in response to external stimuli such as sounds and mechanical forces. The enlarged stretchability is attributed to the two-stage cracking process induced by the synergy of micro-voids and nano-voids. In-situ observation confirms that at low strains micro-voids between nanowire clusters guide the process of crack growth, whereas at large strains new cracks are randomly initiated from nano-voids among individual nanowires.

show abstract

Section: Introductionmentioning

confidence: 99%

Micro-/nano-voids guided two-stage film cracking on bioinspired assemblies for high-performance electronics

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Regarding three-dimensional (3D) systems, the crack front (the leading edge of the crack) should be considered. Local crack speed v l at each point of the crack front is governed by local energy balance G l = Γ l (v l ), and the ensemble of local energy balances in turn controls the whole crack front shape (7,8).…”

mentioning

confidence: 99%

“…However, it may lose stability at high speed and generate 3D markings on the fracture surface (11)(12)(13)(14)(15). A recent study (8) showed that the crack front can develop localized topological defects drifting along the front that lead to faceted fracture surfaces. Elastic waves also perturb the crack front and generate fracture surface undulations.…”

mentioning

confidence: 99%

Self-emitted surface corrugations in dynamic fracture of silicon single crystal

Wang

Fourmeau

Zhao

et al. 2020

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

When a dynamic crack front travels through material heterogeneities, elastic waves are emitted, which perturb the crack and change the morphology of the fracture surface. For asperity-free crystalline materials, crack propagation along preferential cleavage planes is expected to present a smooth crack front and form a mirror-like fracture surface. Surprisingly, we show here that in single crystalline silicon without material asperities, the crack front presents a local kink during high-speed crack propagation. Meanwhile, local oscillations of the crack front, which can move along the crack front, emerge at the front kink position and generate periodic fracture surface corrugations. They grow from angstrom amplitude to a few hundred nanometers and propagate with a long lifetime at a frequency-dependent speed, while keeping a scale-independent shape. In particular, the local front oscillations collide in a particle-like manner rather than proceeding with a linear superposition upon interaction, which presents the characteristic of solitary waves. We propose that such a propagating mode of the crack front, which results from the fracture energy fluctuation at a critical crack speed in the silicon crystal, can be considered as nonlinear elastic waves that we call “corrugation waves.”

show abstract

“…The out of plane distortion is easily detected post mortem through the pattern left on the fracture surfaces. This was observed with chemical gels by Sekimoto et al [115] and Kolvin et al [116] as well as physical ones by Baumberger et al [117,118]. Other characteristic morphological instabilities pertain to crack branching.…”

Section: Crack Front Path Instabilitiesmentioning

confidence: 71%

Environmental control of crack propagation in polymer hydrogels

Baumberger

Ronsin

2020

Mech Soft Mater

View full text Add to dashboard Cite

Hydrogels are highly hydrated polymer networks. The synergistic association of a fluid and an elastic phase is the key of numerous applications of hydrogels as food or cosmetic products, drug delivery vectors, wound dressings, scaffolds for tissue regeneration... Since the natural environment for many of these applications is a wet or liquid one, exchange of fluid or solute may occur via the liquid continuum which exists between the environment and the constitutive solvent. In addition to purely osmotic forces, stresses acting on the network are able to drive solvent flow. This is the basis of poroelasticity, initially studied within the framework of consolidated, fluid saturated rocks. The specificity of hydrogels lies on their high stretchability, which makes extended non-linear elasticity the rule rather than the exception when dealing with fracture mechanics. The association of poro-and non-linear elasticity brings the study of rupture of hydrogels at the forefront of research in mechanics. Along this review, we intend to explore the various ways the environment may affect the nucleation, growth and path stability of a crack in a hydrogel. This goal is pursued from a physicist and experimentalist point of view, with special emphasis on dimensionless relevant parameters and order-of-magnitude estimates. A substantial part of the paper is devoted to an introduction to the specific features of soft gel fracture mechanics. We then try and put forward the wide variety of theoretical and experimental issues relevant to environmental crack control with some tentative insight into tissue engineering and living tissue biomechanics. Keywords Hydrogels • Poroelasticity • Fracture mechanics • Delayed fracture • Drug delivery • Tissue engineering List of main symbols and abbreviations χ Flory parameter for solvent quality δ Crack tip opening displacement Volumetric strain in Eq. (4) η Solvent viscosity Degree of rehydration of the cohesive zone defined in Eq. (43) Fracture energy (generic) 0 Threshold for crack growth int Intrinsic fracture energy visc Viscous dissipation term eff Effective fracture energy dry,wet Fracture energy of a dry (resp. wet) crack κ Darcy permeability ν Drained Poisson ratio λ 3 eq Equilibrium swelling ratio λ 3 0

show abstract

Topological defects govern crack front motion and facet formation on broken surfaces

Cited by 42 publications

References 33 publications

Micro-/nano-voids guided two-stage film cracking on bioinspired assemblies for high-performance electronics

Micro-/nano-voids guided two-stage film cracking on bioinspired assemblies for high-performance electronics

Self-emitted surface corrugations in dynamic fracture of silicon single crystal

Environmental control of crack propagation in polymer hydrogels

Contact Info

Product

Resources

About