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 paper, a low transformation temperature welding wire is used to transform from austenite to martensite at about 180°C and finish it at room temperature, which induces a compressive residual stress around the welded part.
73 citations
TL;DR: In this article, the performance of the selective laser melting (SLM) process on Inconel 718 (IN 718) parts was investigated and it was shown that the direction parallel to the build direction is associated with the lowest fatigue strength.
Abstract: Recent research efforts in additive manufacturing have focused on developing parts made of Inconel 718 (IN 718), a nickel-based superalloy, which is an attractive material for aerospace and energy high-temperature applications. Here the selective laser melting (SLM) process is used to transform alloy powder into a solid IN 718 parts followed by optimal stress-relief and subsequent precipitation hardening treatment. Two main aspects were investigated. The IN 718 microstructure generated by the SLM process was characterized using metallographic techniques and found to be distinctly directional because it is a result of a layer-by-layer material build-up typical of the SLM process. The high cycle fatigue behavior of SLM IN 718 was determined using a novel test method designed to determine and quantify the directional material behavior, which is important information for part design and process optimization. The fatigue S-N data show that the direction parallel to the build direction is associated with the lowest fatigue strength. The role of the as-produced surface characteristics on fatigue crack initiation is discussed.
73 citations
TL;DR: In this article, the effects of the tool pin diameter and tool rotation on the fatigue behavior of FSW lap joints were investigated using a conventional semiautomatic milling machine and the results of the tests performed indicated that an optimisation is required for the studied parameters, in order to obtain reasonable fatigue strength.
Abstract: The objective of this study was to determine the effects of the tool pin diameter and tool rotation on the fatigue behaviour of friction stir welded (FSW) lap joints. FSW lap joints of AA 5754 aluminium alloy plates were produced by means of a conventional semiautomatic milling machine. Consequently, defect free FSW lap joints were produced on alloy plates at a constant traverse speed but with different tool pin diameter and tool rotation. Therefore, within this study, tool rotation and the tool pin diameter were accepted as variable parameters, while others held fixed. The results of the tests performed, indicate that an optimisation is required for the studied parameters, in order to obtain reasonable fatigue strength. An index, related to tool rotation, traverse speed, pin diameter, and pin height can be identified and used to select optimum parameters for FSW applications.
73 citations
TL;DR: In this paper, a review of the models used to predict the cumulative fatigue damage in FRP composites is presented, in terms of fatigue strength and damage growth and are compared with those in the literature.
Abstract: A brief review of the models used to predict the cumulative fatigue damage in FRP composites is presented. Two-stage fatigue loading of a [0/90, ± 45 2 ,0/90] s quasi-isotropic woven carbon fibre/epoxy resin laminate was evaluated at stress ratio R = 0.05 and the failure mechanisms investigated using x-radiography after each loading stage. The results are presented in terms of fatigue strength and damage growth and are compared with those in the literature. A low-to-high loading sequence is more damaging than a high-to-low one and the Palmgren-Miner linear damage rule may no longer be valid for this kind of material, as previously reported.
73 citations
TL;DR: In this paper, the cyclic response of the studied material may be described in terms of three different regimes within the plastic strain amplitude (ϵpl) range investigated, i.e. from 2 × 10−5 to 6 × 10 −3: at ϵpl below 10−4 the dominant cyclic deformation mechanisms are those correlated to planar glide of dislocations within the austenite which is the phase which carries a large part of the macroscopic strain in this first regime.
73 citations