Crack propagation in oxide glasses at low crack velocities is controlled by stress corrosion. Proper knowledge of the crack tip chemical environment is thus crucial to understand the slow fracture process of these materials. The formation of a liquid condensate in the confined area of the crack tip is theoretically expected and is classically mentioned to explain specific behavior during the cr...

Crack formation is typically undesirable as it represents mechanical failure that compromises strength and integrity. Recently, there have also been numerous attempts to control crack formation in materials with the aim to prevent or isolate crack propagation. In this work, we utilize fragmentation, at submicron and nanometre scales, to create ordered metal oxide film coatings. We introduce a s...

A planar crack generically segments into an array of "daughter cracks" shaped as tilted facets when loaded with both a tensile stress normal to the crack plane (mode I) and a shear stress parallel to the crack front (mode III). We investigate facet propagation and coarsening using in situ microscopy observations of fracture surfaces at different stages of quasistatic mixed-mode crack propagatio...

We here report on a detailed experimental study whose goal is to investigate spontaneous crack propagation in bonded and intact materials subjected to quasi-static far-field tensile loading. The cracks nucleate from a tiny circular hole and are triggered by an exploding wire. They subsequently propagate under the action of a constant far-field load. Dynamic photoelasticity in conjunction with h...

We report a novel mode of quasi-static oscillatory crack propagation when a cutting tool is driven through a thin polymer film [6,7]. In our experiments, for tools with a large enough width, the crack tip follows a highly periodic path, leaving behind a striking oscillatory pattern. Taking into account the separation of the film's bending and stretching energies and using classical fracture the...

– The dynamics of planar crack fronts in heterogeneous media is studied using a recently proposed stochastic equation of motion that takes into account nonlinear effects. The analysis is carried for a moving front in the quasi-static regime using the Self Consistent Expansion. A continuous dynamical phase transition between a flat phase and a dynamically rough phase, with a roughness exponent ζ...

Earlier [ 1] we described an experimental procedure aimed at exarnining the spatial and temporal distribution of energy dissipation during crack initiation and propagation in a ductile polymer. The experiment combines a table-top tensile tester and an infrared imaging system. Because of the intense heating of the crack tip region, direct observation of the temperature rise not only provides an ...

RICE et ml. (1994, J. Mech. Ph_vs. Solids 42, 813-843) analyse the propagation of a planar crack with a nominally straight front in a model elastic solid with a single displacement component. Using the form of their results for a strictly linearized perturbation from a straight crack front which moves at uniform speed, we give the corresponding first-order expression for the deviation of a crac...

We investigated the microstructural and fatigue characteristics on consolidated Japanese cedar called “ObiSugi (Cryptomeria japonicain)” fabricated by hot-pressing. Hot-press treatment was conducted at various conditions. Three point bending test, hardness test and plane bending fatigue test of consolidated wood were carried out to investigate mechanical properties. Flexural strength of consoli...

We study experimentally the propagation of an in-plane fracture into a transparent and heterogeneous Plexiglas block. A stable crack propagation in mode I is monitored by an imposed displacement. The experimental setup allows a high resolution observation of the crack front in situ. Self-affine properties of the crack front are described over more than three decades using several techniques: va...