Experiments concerning the morphology of fracture surfaces various materials are reviewed. The observations interpreted within framework models lines moving in a random environment. This suggests that heterogeneous could be seen as dynamic phase transition.

Different rupture modes and different fracture toughness values were obtained on an aluminium alloy subjected to four heat treatments. The correlation functions of the bidimensional cuts fractured surfaces determined. It was found that these fractal, their fractal dimensions identical, within experimental error.

We report in situ atomic force microscopy experiments which reveal the presence of nanoscale damage cavities ahead a stress-corrosion crack tip glass. Their might explain departure from linear elasticity observed vicinity Such ductile fracture mechanism, widely case metallic materials at micrometer scale, be also origin striking similarity morphologies surfaces glass and alloys different length scales.

The self-affine properties of postmortem fracture surfaces in silica glass and aluminum alloy were investigated through the 2D height-height correlation function. They are observed to exhibit anisotropy. roughness, dynamic, growth exponents determined shown be same for two materials, irrespective crack velocity. These conjectured universal.

The fatigue fracture surfaces of a metallic alloy and the stress corrosion silicate glass are investigated as function crack velocity. It is shown that in both cases there two self-affine regimes. At large enough length scales, universal roughness index $\ensuremath{\zeta}\ensuremath{\simeq}0.78$ recovered. smaller exponent close to ${\ensuremath{\zeta}}_{c}\ensuremath{\simeq}0.50$. crossover ${\ensuremath{\xi}}_{c}$ separating these regimes strongly depends on material, exhibits power-law...

We present theoretical ideas which allow us to understand part of the scaling laws recently observed on branched cracks. argue that some features are common all critical structures, barely survive when propagating. These illustrated by directed percolation problem, serves as an excellent toy model. Finally, we propose a Langevin equation for unbranched cracks in three dimensions, naturally leads self-affine structures.

We investigate the scaling properties of postmortem fracture surfaces in silica glass and glassy ceramics. In both cases, 2D height-height correlation function is found to obey Family-Viseck properties, but with two sets critical exponents, particular, a roughness exponent $\ensuremath{\zeta}\ensuremath{\simeq}0.75$ homogeneous $\ensuremath{\zeta}\ensuremath{\simeq}0.4$ The ranges length scales over which these scalings are observed shown be below above size process zone, respectively. A...

Using lithography-based microfluidic technology, we produce monodisperse single-core microcapsules with UV-cured TPGDA (triprophylene glycol diacrylate) shells. We show that the geometrical and mechanical characteristics of can be predicted on a quantitative basis tuned by varying flow conditions. Shell thicknesses are varied changing rates inner or intermediate phases, according to mass conservation constraint. Off-centering core respect shell is controlled phase viscosity. The properties...

Abstract Many faults and fractures in various natural man‐made materials share a remarkable common fractal property their morphology. We report on the roughness of rocks by analyzing out‐of‐plane fluctuations slip surfaces. They display statistical power‐law relationship with nearly constant exponent from millimeter scale micro‐fractures fault zones to coastlines measuring thousands kilometers that have recorded continental breakup. A possible origin this striking over 11 orders magnitude...

We consider the various adsorption regimes of flexible polymer chains in a good solvent when bulk concentration is changed. As latter increased, first we find very dilute regime where surface coverage increases fast. This followed by plateau with much slower increase for Γ, solution being still dilute. In semi-dilute regime, blobs. For high volume fraction, ϕ b > δ4/3, δ dimensionless excess energy per monomer on surface, blobs are not adsorbed. The interfacial tension calculated different...

Small angle neutron scattering experiments were performed on Polyurethane branched polymers synthetized near the gelation threshold. The exponent τ of size distribution function is measured, a system cross-linked by polycondensation. We find = 2.2 ± 0.04. This leads to fractal dimension for in reaction bath Dp 2.5 0.09, agreement with percolation model. In dilute state, D 1.98 0.03, recent predictions. Thus largest are swollen dilution, and behave as lattice animals.

A statistical analysis of fracture surfaces the polycrystalline intermetallic compound ${\mathrm{Ni}}_{3}$Al is reported. Although these contain secondary branches, a roughness exponent \ensuremath{\zeta} can be defined, and found close to 0.8. The number branches shown have nontrivial fluctuations, which exhibit power-law increase with an strongly dependent upon dynamics crack branching during propagation. Moreover, probability distributions both heights averaged are slowly decrease, i.e.,...

Amorphous silica density at ambient pressure is known to depend on thermal history (through the quenching rate) but also, room temperature, maximum applied in past. Here we show that beyond density, a mechanical loading can endow structure with an orientational order. Molecular dynamics simulations evidence amorphous develops permanent anisotropic after extended shear plastic flow. This anisotropy which survives for unstressed specimen revealed markedly by fabric tensor computed over Si-O-Si...

Thin soft elastic layers serving as joints between relatively rigid bodies may function sealants, thermal, electrical, or mechanical insulators, bearings, adhesives. When such a joint is stressed, even though perfect adhesion maintained, the exposed free meniscus in thin layer becomes unstable, leading to formation of spatially periodic digits air that invade layer, reminiscent viscous fingering fluid layer. However, instability reversible and rate-independent, disappearing when unstressed....

We demonstrate experimentally the existence of a purely elastic, nonviscous fingering instability which arises when air penetrates into an elastomer confined in Hele-Shaw cell. Fingers appear sequentially and propagate within bulk material as soon critical strain, independent elastic modulus, is exceeded. Key elements driving force are confinement gel its adhesion to plates cell, result considerable expense energy during growth bubble.

The fracture surfaces of a Zr-based bulk metallic glass exhibit exotic multi-affine isotropic scaling properties. study the mismatch between two facing as function their distance shows that occurs mostly through growth and coalescence damage cavities. fractal nature these cavities is shown to control roughness surfaces.

We review experiments concerning the quantitative morphology of fracture surfaces various materials, at different length scales, using techniques. These could separate "universal" morphological parameters from material-dependent ones. show how these results have been basis theoretical developments on crack propagation and damage in heterogeneous materials.