Abstract The paper contains the results of an experimental investigation fatigue crack development under mixed-mode I + II and III in heat-treated 42CrMo4 steel. Tests were performed on compact tension shear specimens rectangular cross-section for III. Mixed-mode tests conducted 30 60° loading angle, while test was 45°. Additionally, presents fracture analysis path development.

This paper investigates the roles of external loads and specimen geometry on crack path selection in adhesively bonded joints. First, the effect of mixed mode fracture on crack path selection is studied. Using epoxy as an adhesive and aluminum as the adherends, double cantilever beam (DCB) specimens with various T-stress levels are prepared and tested under mixed mode fracture loading. Post-fai...

The dependence of the Weibull stress is investigated on the parameters of the elasticplastic crack tip field. The general form of the Weibull stress is given for a three-parameter approximation of the elasto-plastic crack tip field. This is the basis to define a constraint correction of the critical value of the J-integral for cleavage fracture.

The problem of crack branching and deflection in bi-material system is considered in this paper. The combinations may be piezoelectric-piezoelectric, or piezoelectric and non-piezoelectric. Based on Stroh's formulation for anisotropic material, Green's functions for various bi-material combinations are presented within the framework of two-dimensional electro-elasticity, allowing the crack prob...

The problem of crack path selection in piezoelectric bimaterials is considered in this paper. Based on the Stroh formulation for anisotropic material and GreenÕs functions for piezoelectric bimaterials, the crack problem is expressed in terms of coupled singular integral equations at ®rst, and then the equations are used to solve for stress and electric displacement ®elds numerically. A crack i...

This paper proposes a reliable and cost-effective two-phase methodology to predict crack propagation life in generic two-dimensional (2D) structural components. First, the usually curved fatigue crack path and its stress-intensity factors are calculated at small crack increments in a specialized finite-element software, using automatic remeshing algorithms, special crack tip elements and approp...

This paper describes a fuzzy error correction control system used to navigate a robot along an easily modifiable path in a well-structured environment. An array of Hall sensors mounted on the bottom of a robot gathers sensory information from a path of ferromagnetic disks placed on the ground. This sensory input is processed by an analog-to-digital converter and the output signals are then inpu...

Crack tip shielding phenomena, whereby the "effective crack-driving force" actually experienced at the crack tip is locally reduced, are examined with reference to fatigue crack propagation behavior in metals, composites and ceramics. Sources of shielding are briefly described in terms of mechanisms relying on the production of elastically constrained zones which envelop the crack (zone shieldi...

this paper presents a finite element analysis and its related experimental test of corrugated steel web beams subjected to fatigue loading. a particular focus in this study was set on the fatigue failure arising from the web-to-flange welded joint of the corrugated steel web beam. a detailed three-dimensional finite element model which explicitly includes the geometry of the web-to-flange welds...

In an earlier paper it was suggested that a knowledge of the elastic-stress variation in the neighborhood of an angular corner of an infinite plate would perhaps be of value in analyzing the stress distribution at the base of a V-notch. As a part of a more general study, the specific case of a zero-angle notch, or crack, was carried out to supplement results obtained by other investigators. Thi...