Vibration fatigue

About: Vibration fatigue is a research topic. Over the lifetime, 3460 publications have been published within this topic receiving 46297 citations.

A new method for modelling the support effect under rotating bending fatigue: application to Ti-6Al-4V alloy, with and without shot peening

Abstract: The subject of this paper is to investigate the capability of the relative stress gradient to properly represent the beneficial effect of residual stress states on the fatigue life of Ti-6Al-4V specimens, with notches of different severity. The research was developed considering notched and un-notched specimens with different geometries and different shot-peening treatments. The results were determined by running fatigue experimentation under rotating bending and by developing a novel predictive model based on the relationship between the local fatigue limit and a generalized form of the relative stress gradient, accounting for the peening-induced residual stresses. The proposed tool for fatigue limit estimation was completed by a stochastic analysis, which considered the variability of the involved parameters, in particular the residual stress entity. This made it possible to finally determine the component failure probability in a general, efficient and accurate way.

Fatigue Response and Modelling of Variable Stress Amplitude and Frequency in AS-4/PEEK Composite Laminates, Part 1: Experiments

Abstract: This paper aims to investigate the tension-tension (T-T) fatigue behavior at variable fatigue loadings in AS-4/PEEK composite laminates. Three lay-ups of specimens, such as cross-ply [0/90]4s, quasi-isotropic [0/45/90/-45]2s and angle-ply [±45]4s, were tested at room temperature and moisture. The parameters involved were maximum stress (low and high), frequency (5 Hz and 25 Hz), and stress ratio (R = 0 and 0.2). We received the fatigue life and found that the maximum stress and stress ratio are the two controlling factors on lives, whilst frequency affects significantly in [±45]4s laminates. Next, stiffness and strength degradation were defined to describe the laminate damage process due to cyclic loadings and these experimental data were correlated with suitable models proposed in power function form. From the damage curves we observe that three stages of damage growth can be clearly divided and different failure mechanisms exist among three lay-ups. All these valuable data will be used to predict fatigu...