The phenomenon of fatigue in gears at the tooth root can be a cause of catastrophic failure if not detected in time. Where traditional low-frequency vibration may help in detecting a well-developed crack or a completely failed tooth, a system for early detection of the nucleation and initial propagation of a fatigue crack can be of great use in condition monitoring. Acoustic emission is a poten...

In the present investigation, fatigue crack growth tests under mixed-mode (I and II) overload have been conducted on HSLA steel and subsequently genetic programming has been applied to predict post overload fatigue life. It is observed that the proposed model predicts fatigue life of HSLA steel with reasonable accuracy.

Microstructural degradation is a predominant source of damage in polycrystalline alloys that are commonly used in diverse applications. For early diagnosis and prognosis of failures, it is essential to understand the mechanisms of damage growth specifically in the crack initiation phase, which is still an intriguing phenomenon for scientists due to sensing inaccuracies and modeling uncertaintie...

The Mechanisms of fatigue failure in Ti-6Al-2Sn-4Zr-6Mo forged discs are investigated: the effects forging and machining operations on decoupled. A four-point bend testing approach enabled crack initiation propagation characteristics to be studied at multiple locations around disc periphery. Fatigue performance variation (of ~60%) different positions, behaviour were linked heterogeneous crystal...

The constant amplitude fatigue crack growth life is affected by load ratio which quantifies the influence of mean load. Several research works have been conducted to study the effect of load ratio on crack growth rate through deterministic approach. However, the application of artificial intelligence methods particularly adaptive neuro-fuzzy technique (ANFIS) is lacking. The current research pr...

Modularity in total hip arthroplasty provides multiple benefits to the surgeon in restoring the appropriate alignment and position to a previously damaged hip joint. The vast majority of modern implants incorporate modularity into their design with some implants having multiple modular interfaces. There is the potential for failure at modular junctions because of fretting and crevice corrosion ...

Failures of externally driven compressor crankshafts may sometimes be due to fretting induced fatigue cracks. Fretting is a degradation process which occurs between two faying surfaces where the relative motion between the components is very small. Discoloration, fine o~ide powder, and shallow surface pitting are the definitive signs of fretting and hence relative motion between components. Fra...

In this paper, the fatigue crack initiation in notched single-crystal test specimens of material MD2 is investigated and analysed. A critical plane approach is adopted, in which the total strain ranges on the discrete slip planes are evaluated. Furthermore, a Coffin-Manson type of expression is used to describe the number of cycles to fatigue crack initiation. This relation is determined from a...

Studies on the growth of small cracks have led to the observation that fatigue life of many engineering materials is primarily “crack growth” from micro-structural features, such as inclusion particles, voids, slip-bands or from manufacturing defects. This paper reviews the capabilities of a plasticity-induced crack-closure model to predict fatigue lives of metallic materials using “small-crack...

A B S T R A C T Various analogies have recently been proposed for comparing the stress fields induced in fretting fatigue contact situations, with those of a crack and a sharp or a rounded notch, resulting in a degree of uncertainty over which model is most appropriate in a given situation. However, a simple recent approach of Atzori–Lazzarin for infinite-life fatigue design in the presence of ...