In the present investigation, an attempt has been made to use “exponential model” in the prediction of fatigue life without integrating the fatigue crack growth rate curve (FCGR). The obtained results are compared with experimental crack growth data obtained for 2024-T351 aluminum alloy for four bending V-Charpy specimens under constant amplitude loading in stress ratio range from 0.1 to 0.3 an...

The fatigue growth of a fiber reinforced composite laminate was characterized under thermal cycling using a combined experimental and computational investigation. Twenty-four ply composite laminates (1⁄20 12=90 12 ) are fabricated with a pre-existing delamination, and subjected to thermal cycling in an environmental chamber. The large mismatch in the coefficients of thermal expansion is used to...

A major part of fracture mechanics is concerned with studying the initiation and propagation of fatigue cracks. This typically requires constant monitoring of crack growth during fatigue cycles and the knowledge of the precise location of the crack tip at any given time. One technique currently available for measuring fatigue crack length is the Potential Drop method[1]. The method, however, ma...

Fatigue crack growth can be strongly influenced by crack closure, i. e., the contacting of the opposing faces of a fatigue crack above the minimum load in a loading cycle. This crack closure shields the crack tip from the full stress field, but different views are held regarding the extent of this shielding. The type of closure, whether it be plasticity-induced, or roughness-induced may also pl...

Understanding the fatigue crack growth phenomenon in railheads requires a study of driving forces such as the crack tip opening and sliding displacements, under repeated rolling contact. Finite element simulations, allowing elastic-plastic deformation, and mixed-mode crack growth laws were utilized to demonstrate that the fatigue crack growth rates display a minimum after a finite amount of cra...

In this study, hydrogen-assisted fatigue propagation (a kind of corrosion phenomenon) in corner cracks at holes located plates under tensile loading was studied, the results compared with those obtained for by air. To end, numerical modeling carried out case studied to evaluate advance crack front based on Paris equation and stress intensity factors (SIFs) Raju Newman. The showed that tended to...

Fatigue cracking is one of the most common failure modes of various load-bearing structures. Even though sensors of many different types have been developed for crack detection, very few can monitor crack growth with a high sensitivity. This paper presents an antenna sensor that is capable of monitoring the growth of fatigue cracks with a sub-millimeter resolution. According to microstrip patch...

A major drawback in using bulk metallic glasses (BMGs) as structural materials is their extremely poor fatigue performance. One way to alleviate this problem is through the composite route, in which second phases are introduced into the glass to arrest crack growth. In this paper, the fatigue crack growth behavior of in situ reinforced BMGs with crystalline dendrites, which are tailored to impa...

Serial mechanical sectioning and high resolution X-ray tomography have been used to study the three-dimensional morphology of small fatigue cracks growing in a 12 Cr tempered martensitic steam turbine blade material. A range of surface conditions has been studied, namely polished and shot peened (with varying levels of intensity). In the polished (unpeened) condition, inclusions (alumina and ma...

First row rotating blades of four axial-flow compressors were prematurely fractured. Previous investigations showed that the site atmosphere contains corrosive compounds which lead to an increase in possibility of pitting on the blades. It was also revealed that the crack was originated from two corrosion pits. Thus, this work is conducted to ascertain which of fatigue or stress corrosion crack...