Various theories in the past have addressed the correlation of material properties and the respective acoustic emission release during fracture. Whilst these theories yield good predictions for fundamental relationships, they neglect the dynamic displacements during crack formation. This paper presents first results for a new acoustic emission crack source model based on a finite element modell...

Water molecules play a fundamental role in the physics of slow crack propagation in glasses. It is commonly understood that, during stress-corrosion, water molecules that move in the crack cavity effectively reduce the bond strength at the strained crack tip and, thus, support crack propagation. Yet the details of the environmental condition at the crack tip in moist air are not well determined...

The presented work introduces a numerical parametric study on the crack propagation direction under mixed-mode conditions (mode I + II). It is conducted for the geometry of an eccentric asymmetric fourpoint bending of a single edge notched beam specimen; various levels of mode-mixity are ensured by modifications in the crack length and crack eccentricity. The direction of crack propagation is e...

To perform crack propagation in a solid model, a high computational power is required, mainly at three-dimensional mesh generation and structural analysis steps. At each crack propagation step, the mesh is rebuilt and a new structural analysis is performed. If a large scale cracked model is being analyzed, time consumed by mesh generation and analysis may be extremely large or even prohibitive ...

A two-dimensional numerical model of microstructural e ects in brittle fracture is presented, with an aim towards the understanding of toughening mechanisms in polycrystalline materials such as ceramics. Quasi-static crack propagation is modelled using the extended nite element method (X-FEM) and microstructures are simulated within the framework of the Potts model for grain growth. In the X-FE...

This study evaluated the tradeoffs amongst fatigue crack propagation resistance, wear resistance, and oxidative stability in a wide variety of clinically-relevant cross-linked ultra-high molecular weight polyethylene. Highly cross-linked re-melted materials showed good oxidation and wear performance, but diminished fatigue crack propagation resistance. Highly cross-linked annealed materials sho...

In this paper, a Paris law-based model is presented whereby crack propagation occurs under cyclic loading in air (fatigue) and in an aggressive environment (corrosion-fatigue) for the case of corner cracks (with a wide range of aspect ratios in the matter of the initial cracks) in finite-thickness plates of 316L austenitic stainless steel subjected to tension, bending, or combined (tension + be...

When a femtosecond laser pulse is focused inside a LiF single crystal, four cracks are generated in the <100> directions from the photoexcited region. The time-resolved observation have elucidated that the tensile stress in the laser induced stress wave induces the generation and propagation of the cracks. In this study, to investigate the possibility of control of laser induced cracks inside s...

This paper is aimed at presenting a partition of unity method for the simulation of three-dimensional dynamic crack propagation. The method is a variation of the partition of unity ®nite element method and hp-cloud method. In the context of crack simulation, this method allows for modeling of arbitrary dynamic crack propagation without any remeshing of the domain. In the proposed method, the ap...

The propagation of an interfacial crack front along the weak plane of a thin film stack is considered. A simple patterning technique is used to create a toughness contrast within this perfectly two-dimensional weak interface. The transparency of the specimens allows us to directly observe the propagation of the purely planar crack obtained during a DCB (Double Cleavage Beam) test. The effect on...