In the current study, the effect of such parameters as the length, position and angle of crack on free vibrations of a cracked plate was examined by finite element method. The assumed crack was internal and through and its growth was ignored. In the proposed finite element model, crack was considered as a discontinuity on the plate surface and the results were compared with the results of other...

The experimental determination of fracture mechanical properties of interface cracks is a substantial task for the design for reliability of electronic packages. As interface cracks are dominated by a mode mix between tension and shear mode (crack driving modes I and II) a mixed mode bending method was developed to adjust the ratio of the two modes (mode mixity). For a correct extraction of an ...

In the aerospace and aviation sectors, the damage tolerance concept has been applied widely so that the modeling analysis of fatigue crack growth has become more and more significant. Since the process of crack propagation is highly nonlinear and determined by many factors, such as applied stress, plastic zone in the crack tip, length of the crack, etc., it is difficult to build up a general an...

An understanding of the evolution of toughness is essential for the mechanistic interpretation of the fracture of cortical bone. In the present study, in vitro fracture experiments were conducted on human cortical bone in order to identify and quantitatively assess the salient toughening mechanisms. The fracture toughness was found to rise linearly with crack extension (i.e., rising resistance-...

A continuum model based upon the Peierls-Nabarro description of a dislocation ahead of a crack is used to evaluate the critical mode I loading for dislocation nucleation at the tip of a finite, pre-blunted crack. A similar approach is used to evaluate the critical mode I loading for atomic decohesion. Results are presented for various crack tip root radii (a measure of bluntness), for several c...

In 2004, a team comprised of researchers and service providers launched the Safer Crack Use, Outreach, Research and Education (SCORE) project in the Downtown Eastside of Vancouver, British Columbia, Canada. The project was aimed at developing a better understanding of the harms associated with crack cocaine smoking and determining the feasibility of introducing specific harm reduction strategie...

Fatigue crack growth is a complex process that involves interactions between many elements ranging across several length scales. This work provides an in-depth, experimental study of fatigue crack growth and the relationships between four of these elements: strain field, microstructure, crack path, and crack growth rate. Multiple data sets were acquired for fatigue crack growth in a nickel-base...

Using cold working fastener holes is a simple life enhancement procedure that strengthens metallic components by retarding crack growth around a hole. In the present paper, the residual stress field that is induced by the hole expansion process is obtained based on different material models namely elastic perfect plastic, isotropic hardening and kinematic hardening using three-dimensional finit...

The stress field at the tip of a crack of a thin plate of elastic material that is broken due to a mode III shear tearing has a universal form with a nonuniversal amplitude, known as the stress intensity factor, which depends on the crack length and the boundary conditions. We present in this paper exact analytic results for this stress intensity factor, thus enriching the small number of exact...