Topic
Fatigue limit
About: Fatigue limit is a research topic. Over the lifetime, 20489 publications have been published within this topic receiving 305744 citations. The topic is also known as: endurance limit & fatigue strength.
Papers published on a yearly basis
Papers
More filters
TL;DR: In this article, the effect of shot peening on the reverse bending fatigue behavior of Al-7075-T651 was investigated by means of X-ray diffraction (XRD) measurements.
143 citations
TL;DR: In this paper, acoustic emission (AE) measurements along the gauge length indicated important critical intra and inter laminar damage occurring as early as 27% of ultimate tensile strength (UTS), typically 0.3% ultimate strain, for laminates with 90° layers.
142 citations
15 Jan 2010-Materials Science and Engineering A-structural Materials Properties Microstructure and Processing
TL;DR: The high cycle fatigue performance of 7050-T7451 aluminum was investigated for untreated as-machined, laser peened, and shot peened conditions Constant amplitude, smooth fatigue tests were conducted in four-point bending at a stress ratio of R = 1 as mentioned in this paper.
Abstract: The high cycle fatigue performance of 7050-T7451 aluminum was investigated for untreated as-machined, laser peened, and shot peened conditions Constant amplitude, smooth (Kt = 1) fatigue tests were conducted in four-point bending at a stress ratio of R = 01 Results show that laser peening induces a layer of compressive residual stress more than three times deeper than for shot peening Both treatments significantly increase fatigue performance At a moderate level of stress, peened specimens outlast as-machined specimens, by a factor of 79 for laser peening and 29 for shot peening At higher stress, life improvements are lower, a factor of 33 for laser peening and 21 for shot peening At a 100,000-cycle lifetime, fatigue strength of laser peened specimens is 41% higher than as-machined specimens and the fatigue strength of shot peened specimens 30% higher than as-machined A form of pitting was noted on the laser peened surfaces and follow-on tests assessed the effects of the pitting on fatigue performance Results indicate that the pitting does not significantly influence fatigue performance
142 citations
TL;DR: In this paper, a pore-sensitive model based on a modified stress-life approach has been developed which correlates fatigue life with the size of the failure-dominant pore.
Abstract: Fatigue strength optimization of cast aluminium alloys requires an understanding of the role of micropores resulting from the casting process. High cycle fatigue tests conducted on cast A3 56-T6 show that the pore size and proximity to the specimen surface significantly influence fatigue crack initiation. This is supported by finite element analyses (both elastic and elastic-plastic) which demonstrate that high stress/strain concentration is induced by pores which are both large and near to the specimen surface. A new pore-sensitive model based on a modified stress-life approach has been developed which correlates fatigue life with the size of the failure-dominant pore. The model prediction is in good agreement with experimental data.
142 citations
TL;DR: In this article, the multi-axial fatigue strength of notched specimens made of 39NiCrMo3 hardened and tempered steel was investigated under two nominal load ratios, R=−1 and R= 0, taking into account the influence of the biaxiality ratio, λ=τa/σa.
Abstract: The paper deals with the multi-axial fatigue strength of notched specimens made of 39NiCrMo3 hardened and tempered steel. Circumferentially V-notched specimens were subjected to combined tension and torsion loading, both in-phase and out-of-phase, under two nominal load ratios, R=−1 and R= 0, also taking into account the influence of the biaxiality ratio, λ=τa/σa. The notch geometry of all axi-symmetric specimens was a notch tip radius of 0.1 mm, a notch depth of 4 mm, an included V-notch angle of 90° and a net section diameter of 12 mm. The results from multi-axial tests are discussed together with those obtained under pure tension and pure torsion loading on plain and notched specimens. Furthermore the fracture surfaces are examined and the size of non-propagating cracks measured from some run-out specimens at 5 million cycles. Finally, all results are presented in terms of the local strain energy density averaged in a given control volume close to the V-notch tip. The control volume is found to be dependent on the loading mode.
141 citations