Academic literature on the topic 'Shock fatigue'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the lists of relevant articles, books, theses, conference reports, and other scholarly sources on the topic 'Shock fatigue.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Journal articles on the topic "Shock fatigue"

1

Yamaguchi, Kenji, Itaru Matsumoto, Tsuyoshi Fujita, Yasuo Kondo, Satoshi Sakamoto, and Mitsugu Yamaguchi. "Evaluation of the Thermal Shock Fatigue Resistance of Cutting Tools Using a CO2 Pulse Laser Beam." Key Engineering Materials 719 (November 2016): 109–13. http://dx.doi.org/10.4028/www.scientific.net/kem.719.109.

Full text
Abstract:
It is well-known that a series of cracks sometimes gets initiated perpendicular to the cutting edges on the rake faces of brittle cutting tools made of materials such as cemented carbide, ceramics, and cermet under high-speed intermittent cutting. The tools used in intermittent cutting processes are exposed to elevated temperatures during cutting and then cool quickly during the noncutting time. Previous studies have suggested that such repeated thermal shocks generate thermal stress in the tool and that the thermal cracks are then propagated by thermal fatigue. Recently, high-speed machining techniques have attracted the attention of researchers. To apply new cutting tool materials to this machining process, it is important to evaluate their thermal shock fatigue resistances. During high-speed intermittent cutting, the frequency of thermal shocks becomes high and the action area of the thermal shocks is limited to the rake face of the tool. Therefore, conventional thermal shock resistance evaluation methods are unsuitable for this case. Consequently, the authors have developed a new experimental evaluation method using a CO2 laser beam. In this study, we irradiated cemented carbide and TiN cermet cutting tools with the CO2 pulse laser beam and gauged the effectiveness of the proposed thermal shock fatigue resistance evaluation method. The results show a correlation between the thermal shock due to the CO2 pulse laser beam and those due to the intermittent cutting experiments.
APA, Harvard, Vancouver, ISO, and other styles
2

Sikhamov, Ruslan, Fedor Fomin, Benjamin Klusemann, and Nikolai Kashaev. "The Influence of Laser Shock Peening on Fatigue Properties of AA2024-T3 Alloy with a Fastener Hole." Metals 10, no. 4 (April 9, 2020): 495. http://dx.doi.org/10.3390/met10040495.

Full text
Abstract:
The objective of the present study was to estimate the influence of laser shock peening on the fatigue properties of AA2024-T3 specimens with a fastener hole and to investigate the possibility to heal the initial cracks in such specimens. Fatigue cracks of different lengths were introduced in the specimens with a fastener hole before applying laser shock peening. Deep compressive residual stresses, characterized by the hole drilling method, were generated into the specimens by applying laser shock peening on both sides. Subsequently, the specimens were subjected to fatigue tests. The results show that laser shock peening has a positive effect regarding the fatigue life improvement in the specimens with a fastener hole. In addition, laser shock peening leads to a healing effect on fatigue cracks. The efficiency of this effect depends on the initial crack length. The effect of laser shock peening on the fatigue life periods was determined by using resonant frequency graphs.
APA, Harvard, Vancouver, ISO, and other styles
3

Czop, Piotr, and Damian Slawik. "Validation of Fatigue Model of a Hydraulic Shock Absorber Equipped with Shim Stack Valves." Journal of Physics: Conference Series 2184, no. 1 (March 1, 2022): 012057. http://dx.doi.org/10.1088/1742-6596/2184/1/012057.

Full text
Abstract:
Abstract The aim of the paper is to formulate and validate the fatigue model of a shock absorber equipped with shim-based clamped valves. The fatigue model has application potential in a virtual valve system pre-selection process during the shock absorber design and configuration stage. It allows the required testing capacity at shock absorber manufacturers to be significantly reduced, i.e. the number of long-term and expensive fatigue tests performed on servo-hydraulic load frame testers. The shock absorber fatigue model is a combination of the previously developed finite element model [1] and analytical routines using the experimentally derived Wöhler characteristics of shim materials [2]. The fatigue model validation process was conducted with a high-performance servo-hydraulic load frame tester. Six shock absorbers were subjected to the same long-cycle kinematic sine-load and tested until initial valve damage symptoms appeared. The paper reports the fatigue calculation process and validation results. The obtained model accuracy in the range of ±30% error of shock absorber life-time prediction. This result is accurate enough for the model to be recommended as a quick-and-dirty engineering tool saving shock absorber development costs.
APA, Harvard, Vancouver, ISO, and other styles
4

Pretorius, Jan G., Dawood A. Desai, and Glen C. Snedden. "Effect of Laser Shock Peening on Fatigue Life at Stress Raiser Regions of a High-Speed Micro Gas Turbine Shaft: A Simulation Based Study." International Journal of Engineering Research in Africa 45 (November 2019): 15–27. http://dx.doi.org/10.4028/www.scientific.net/jera.45.15.

Full text
Abstract:
Fatigue failure due to stress raiser regions on critical rotating components in gas turbine engines, such as the shaft, is a crucial aspect. Methods to reduce these stresses and improve fatigue life are a source of ongoing research. Laser shock peening is a method where compressive residual stresses are imparted on the stress raisers of such components. However, numerical based studies on multiple laser shock peening applied to stress raisers is under-researched. Hence, this study will attempt to predict the fatigue life at fillet radii step induced stress raiser regions on a high-speed gas turbine engine shaft by utilization of laser shock peening. The objective of this study was achieved by developing a more computational efficient finite element model to mimic the laser shock peening process on the fillet radii step induced stress raiser regions of a shaft. A modified laser shock peening simulation method for effective prediction of the residual stress field was introduced. Furthermore, the fatigue life improvement due to laser shock peening was predicted by employing Fe-safe fatigue software. From the results, the modified laser shock peening simulation method provided accurate prediction of the residual stress field with a reduced computational time of over 68% compared to conventional methods. The fatigue life revealed an improvement of 553% due to laser shock peening, which is comparable to similar findings in the literature. Hence, from the findings and results achieved, the developed finite element model can be an appropriate tool to assist in the fatigue life estimation of laser shock peening applied to stress raisers.
APA, Harvard, Vancouver, ISO, and other styles
5

Ren, Xu Dong, Yong Kang Zhang, Y. H. Li, W. Cheng, and M. Zhuang. "Mechanism Influence on Fatigue Characters of Aerial Engine Blade by Laser Shock Processing." Advanced Materials Research 24-25 (September 2007): 371–75. http://dx.doi.org/10.4028/www.scientific.net/amr.24-25.371.

Full text
Abstract:
In Laser Shock Processing when a material is irradiated with short laser pulses (ns)of very high densities(>GW/cm2), a high intensity shock wave is generated. This treatment can reduce the rate of fatigue cracking and stress corrosion cracking in structural metals or alloys needed for aerospace, nuclear power plants, and military applications. And laser shock processing has been shown to be a viable method of strengthen metallic components. Transformation on the characters of aerial engine blade by laser shock processing and influence on the fatigue life with these transformations were studied. And the relatively fatigue life experiment of aerial engine blade was done to validate the influence on the fatigue life of aerial engine by laser shock processing. It was found that laser shock processing could bring residual compressive stress and high-density dislocation on the surface of the blade. All these transformation greatly increase the fatigue life of aerial engine blade.
APA, Harvard, Vancouver, ISO, and other styles
6

Chiang, C. K., C. L. Yang, W. C. Chen, C. H. Chang, S. C. Huang, and J. L. Wang. "Shock Attenuation of Intervertebral Disc Following Fatigue Loading." Journal of Mechanics 27, no. 1 (March 2011): 9–17. http://dx.doi.org/10.1017/jmech.2011.2.

Full text
Abstract:
ABSTRACTShock absorption is one of the fundamental biomechanical functions of disc. The knowledge of the effect of fatigue loading, impact energy and contact period on the disc shock attenuation is important in clarifying the risk factors of back pain and evaluating the efficacy of novel disc prosthesis. The purpose of this study is to find the changes of shock attenuation of motion segment after fatigue loading, and the effect of impact energy and contact period on the disc shock attenuation pre and post fatigue loading.The 3-unit porcine spinal motion segment was used for testing. The impact test was applied pre and post fatigue loading. Impact energy and contact period were controlled in the experiment. Shock attenuation properties, including the acceleration attenuation (AA) of disc, force transmissibility (FT) and phase delay of force (PDF) of motion segment, were calculated from the acceleration and force responses.The results showed that the shock attenuation properties (acceleration attenuation and force transmissibility) decreased post fatigue. The disc acceleration attenuation was independent of impact energy and contact period. The disc acceleration attenuation was 0.78 (−1.06dB) pre fatigue and 1.04 (0.14dB) post fatigue. The force transmissibility of motion segment decreased post fatigue only during short contact period. The phase delay of force did not change significantly post fatigue.We found that the fatigue loading decreased the disc shock attenuation. The disc was at higher risk of injury following fatigue loading even at a mild impact loading. The disc acceleration attenuation was invariant of impact energy and contact period, but decreased post fatigue. The disc acceleration attenuation is a good index to evaluate the degree of fatigue injury.
APA, Harvard, Vancouver, ISO, and other styles
7

Ren, Xu Dong, Yong Zhuo Huangfu, Yong Kang Zhang, Da Wei Jiang, and Tian Zhang. "Fatigue Crack Propagation Experiment and Simulation on 7050 Aluminum Alloy." Key Engineering Materials 464 (January 2011): 560–63. http://dx.doi.org/10.4028/www.scientific.net/kem.464.560.

Full text
Abstract:
In this paper, an experiment of fatigue crack propagation in 7050 aluminum alloy was presented. Laser shock processing (LSP) is used to shock the crack surface. Compared with the specimen without LSP, the fatigue life after LSP increased greatly. The simulation of the fatigue crack growth in 7050 aluminum alloy is implemented in FRANC2D. Simulating result is in accordance with the result of the experiment well. Laser shock processing increases the fatigue life and reduce fatigue crack growth rate, it has good prospect on the study of crack arrestment.
APA, Harvard, Vancouver, ISO, and other styles
8

MAEKAWA, Ichiro, Hiroshi SHIBATA, Akira KOBAYASHI, and Tsutomu WADA. "Thermal shock fatigue of Al2O3 ceramics." Journal of the Society of Materials Science, Japan 38, no. 429 (1989): 658–62. http://dx.doi.org/10.2472/jsms.38.658.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Wolfenden, A., JL Yuen, and RJ Walter. "Thermal Shock and Thermal Fatigue Testing." Journal of Testing and Evaluation 19, no. 5 (1991): 403. http://dx.doi.org/10.1520/jte12594j.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Verbitsky, Oleg, Joseph Mizrahi, Arkady Voloshin, July Treiger, and Eli Isakov. "Shock Transmission and Fatigue in Human Running." Journal of Applied Biomechanics 14, no. 3 (August 1998): 300–311. http://dx.doi.org/10.1123/jab.14.3.300.

Full text
Abstract:
The goal of this research was to analyze the effects of fatigue on the shock waves generated by foot strike. Twenty-two subjects were instrumented with an externally attached, lightweight accelerometer placed over the tibial tuberosity. The subjects ran on a treadmill for 30 min at a speed near their anaerobic threshold. Fatigue was established when the end-tidal CO2pressure decreased. The results indicated that approximately half of the subjects reached the fatigue state toward the end of the test. Whenever fatigue occurred, the peak acceleration was found to increase. It was thus concluded that there is a clear association between fatigue and increased heel strike–induced shock waves. These results have a significant implication for the etiology of running injuries, since shock wave attenuation has been previously reported to play an important role in preventing such injuries.
APA, Harvard, Vancouver, ISO, and other styles

Dissertations / Theses on the topic "Shock fatigue"

1

Thomas, Judith A. "Heat shock does not attenuate low frequency fatigue." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape16/PQDD_0015/MQ28673.pdf.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Turner-Adomatis, Bonnie L. "Shock-enhanced sintering of silicon nitride." Thesis, Georgia Institute of Technology, 1995. http://hdl.handle.net/1853/18905.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Taddia, Sara <1986&gt. "Effect of Laser Shock Peening on Fatigue Crack Propagation of Aeronautical Structures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7130/1/Taddia_Sara_tesi.pdf.

Full text
Abstract:
Laser Shock Peening (LSP) is a surface enhancement treatment which induces a significant layer of beneficial compressive residual stresses up to several mm underneath the surface of metal components in order to improve the detrimental effects of crack growth behavior rate in it. The aim of this thesis is to predict the crack growth behavior of thin Aluminum specimens with one or more LSP stripes defining a compressive residual stress area. The LSP treatment has been applied as crack retardation stripes perpendicular to the crack growing direction, with the objective of slowing down the crack when approaching the LSP patterns. Different finite element approaches have been implemented to predict the residual stress field left by the laser treatment, mostly by means of the commercial software Abaqus/Explicit. The Afgrow software has been used to predict the crack growth behavior of the component following the laser peening treatment and to detect the improvement in fatigue life comparing to the specimen baseline. Furthermore, an analytical model has been implemented on the Matlab software to make more accurate predictions on fatigue life of the treated components. An educational internship at the Research and Technologies Germany- Hamburg department of Airbus helped to achieve knowledge and experience to write this thesis. The main tasks of the thesis are the following: -To up to date Literature Survey related to laser shock peening in metallic structures -To validate the FE models developed against experimental measurements at coupon level -To develop design of crack growth slow down in centered and edge cracked tension specimens based on residual stress engineering approach using laser peened patterns transversal to the crack path -To predict crack growth behavior of thin aluminum panels -To validate numerical and analytical results by means of experimental tests.
APA, Harvard, Vancouver, ISO, and other styles
4

Taddia, Sara <1986&gt. "Effect of Laser Shock Peening on Fatigue Crack Propagation of Aeronautical Structures." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2015. http://amsdottorato.unibo.it/7130/.

Full text
Abstract:
Laser Shock Peening (LSP) is a surface enhancement treatment which induces a significant layer of beneficial compressive residual stresses up to several mm underneath the surface of metal components in order to improve the detrimental effects of crack growth behavior rate in it. The aim of this thesis is to predict the crack growth behavior of thin Aluminum specimens with one or more LSP stripes defining a compressive residual stress area. The LSP treatment has been applied as crack retardation stripes perpendicular to the crack growing direction, with the objective of slowing down the crack when approaching the LSP patterns. Different finite element approaches have been implemented to predict the residual stress field left by the laser treatment, mostly by means of the commercial software Abaqus/Explicit. The Afgrow software has been used to predict the crack growth behavior of the component following the laser peening treatment and to detect the improvement in fatigue life comparing to the specimen baseline. Furthermore, an analytical model has been implemented on the Matlab software to make more accurate predictions on fatigue life of the treated components. An educational internship at the Research and Technologies Germany- Hamburg department of Airbus helped to achieve knowledge and experience to write this thesis. The main tasks of the thesis are the following: -To up to date Literature Survey related to laser shock peening in metallic structures -To validate the FE models developed against experimental measurements at coupon level -To develop design of crack growth slow down in centered and edge cracked tension specimens based on residual stress engineering approach using laser peened patterns transversal to the crack path -To predict crack growth behavior of thin aluminum panels -To validate numerical and analytical results by means of experimental tests.
APA, Harvard, Vancouver, ISO, and other styles
5

Spanrad, Sven Klaus. "Fatigue crack growth in laser shock peened aerofoils subjected to foreign object damage." Thesis, University of Portsmouth, 2011. https://researchportal.port.ac.uk/portal/en/theses/fatigue-crack-growth-in-laser-shock-peened-aerofoils-subjected-to-foreign-object-damage(b367cb9f-b746-4c27-9479-49cd48999519).html.

Full text
Abstract:
Foreign Object Damage (FOD) is one of the main life limiting factors for aeroengine fan blades. The FOD impacts during takeoff and landing cause severe damage to aerofoils, resulting in reduced air safety and life time with an estimated annual cost of $4 billion for the aeroengine industry. Advanced surface treatments, such as Laser Shock Peening (LSP) have significantly improved the fatigue strength and crack growth resistance of critical components under FOD. However, it is not yet possible to predict the protective residual stresses and utilise their full potential for enhancing fatigue resistance and damage tolerance capacity in service. This research programme aims to utilise some of the established methods for fatigue tolerance assessment of critical components, based on fracture mechanics principles, to address the effects of complex residual stresses due to LSP and FOD on fatigue crack growth in aerofoils under simulated service loading conditions. The experimental study involved fatigue testing of LSPed and FODed specimens with a geometry representative of fan blades made from Ti-6Al-4V alloy. A four point bend fatigue test setup was designed and calibrated. A real-time computer-controlled crack growth monitoring system and optical crack monitoring techniques were developed. Scanning Electron Microscopy (SEM) and Back-Scatter Electron (BSE) were used to conduct metallographic and fractographic studies, including crack initiation, early fatigue crack growth and FOD damage characterisation. The fracture mechanics analyses used the weight function method and the finite element method to obtain a modified stress intensity factor considering residual stresses due to LSP and FOD. Fatigue crack growth data under low cycle fatigue(LCF), high cycle fatigue (HCF) and combined LCF and HCF loading conditions were correlated using a standard and the modified stress intensity factors. The influence of impact angles and loading conditions on fatigue crack growth behaviour was assessed, and the results were compared with those from untreated FODed specimens.
APA, Harvard, Vancouver, ISO, and other styles
6

Chaswal, Vibhor. "A study of Laser Shock Peening on Fatigue behavior of IN718Plus Superalloy: Simulations and Experiments." University of Cincinnati / OhioLINK, 2013. http://rave.ohiolink.edu/etdc/view?acc_num=ucin1368027477.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Giandolini, Marlène. "Gestion de l'impact et de la fatigue neuromusculaire en trail running." Thesis, Saint-Etienne, 2015. http://www.theses.fr/2015STET009T/document.

Full text
Abstract:
Bien que constitué anatomiquement et physiologiquement pour la course d’endurance, l’Homme est considérablement exposés à diverses blessures musculo-squelettiques liées à la répétition de contraintes mécaniques. Le coureur de trail running par exemple est soumis à de nombreux impacts ainsi qu’à une fatigue et des dommages musculaires sévères. Ces chocs répétitifs et dommages musculaires réduiraient la tolérance du coureur face aux contraintes mécaniques le poussant ainsi à altérer sa cinématique de course. Par conséquent, minimiser les dommages musculo-squelettiques serait déterminant pour la performance en trail running. Des évidences montrent que la pose de pied altère la localisation et l’intensité des contraintes appliquées au système musculo-squelettique. L’objectif de ce travail de thèse a été d’étudier l’influence du pattern de pose de pied sur l’impact et la fatigue neuromusculaire en trail running. Les phases de descente ont été tout particulièrement étudiées du fait qu’elles sont les plus traumatisantes. En effet, ce travail de thèse a mis en évidence qu’en situation de trail running, l’intensité de l’impact augmente lorsque la pente diminue, et que la fatigue neuromusculaire périphérique est aussi sévère à la suite d’une descente isolée qu’après un ultra-trail de plusieurs heures. En étudiant l’influence de la pose de pied adoptée au cours d’une descente en situation de trail running, il a été observé qu’attaquer le sol par l’avant du pied augmentait la fatigue neuromusculaire aux extenseurs du genou. Cependant, une importante variabilité dans les patterns de pose de pied adoptés au cours de la descente a été associée à une baisse de la fatigue neuromusculaire aux extenseurs du genou et fléchisseurs plantaires. L’influence de la pose de pied sur l’intensité du choc et le contenu vibratoire le long des axes axial et transversal a également été démontrée : adopter une attaque talon diminue la sévérité du choc axial mais réduit l’intensité du choc transversal. La principale conclusion est qu’aucun pattern de course ne saurait être universellement recommandé du fait que « changer de pose de pied » est synonyme de « changer la localisation et la magnitude des contraintes appliquées au système musculo-squelettique ». En ce sens, alterner entre différents patterns de course serait une stratégie efficiente en trail running
Although Humans are “born” anatomically and physiologically adapted to long distances run, they are substantially exposed to various musculoskeletal overuse injuries. Trail runners sustain a high number of foot-to-ground contacts and develop severe muscle fatigue and damages. Repetitive shocks and muscle damages would reduce the runners’ tolerance to mechanical strains leading to changes in running kinematics. Minimizing musculoskeletal damages is therefore considered paramount for performance in trail running. Numerous studies highlighted that the foot strike pattern alters the localization and magnitude of the mechanical strains applied on the musculoskeletal system. The main purpose of this thesis was to study the influence of the foot strike pattern on impact and neuromuscular fatigue in trail running. Downhill sections were mainly investigated since they are the most mechanically stressful. Indeed, it was observed from this thesis’ work that, in real trail running practice, the impact intensity increases as the slope decreases, and that the neuromuscular fatigue induced by a single downhill run is as severe as the one induced by an ultratrail race that lasts several hours. Investigating the effect of the foot strike pattern adopted during a downhill trail run on fatigue, it was observed that forefoot striking increases the neuromuscular fatigue at knee extensors. However, a high variability in foot strike patterns adopted was associated to a lower neuromuscular fatigue at both knee extensors and plantar flexors. The effect of the foot strike pattern on axial and transversal shock and vibration content was also demonstrated: heel striking was correlated to a lower impact severity along the axial axis of the skeleton but a greater one along its transversal axis. The main conclusion of this thesis is that no single foot strike pattern should be universally advised due to “changing of foot strike” means “changing the localization and magnitude of the mechanical stress applied on the musculoskeletal system”. Switching between different running patterns might be an efficient strategy in trail running
APA, Harvard, Vancouver, ISO, and other styles
8

Becker, Alexander. "The effect of laser shock peening and shot peening on the fatigue performance of aluminium alloy 7075." Master's thesis, University of Cape Town, 2017. http://hdl.handle.net/11427/25161.

Full text
Abstract:
It has been well established that most fatigue cracks initiate from stress concentration sites found on the surfaces of components subject to cyclic fatigue loading. The introduction of residual compressive stresses into the surface layers of components, through various means including shot peening and laser shock peening, can result in local residual compressive stresses which provide a resistance to both crack initiation and propagation, thus leading to an increase in the fatigue life of the components. The effects of both laser shock peening (LSP) and conventional shot peening (SP) on the fatigue properties of both 7075-T6 and 7075-T0 aluminium round bar test specimens were investigated and compared by means of cyclic 3-point bend fatigue testing. This investigation focused on the role that the peening induced microstructure, surface morphology and hardness had on the fatigue life of the test specimens. It was found that both the laser shock peening and shot peening processes substantially increased the fatigue lives compared to unpeened AA7075-T6. The laser shock peening process more than doubled the fatigue life of the specimens and the shot peening process increased the fatigue life by approximately 1.6×. No discernible hardening effects could be determined in the laser shock peened specimens. However, the shot peening process resulted in a distinct hardened region within the surface layers of the AA7075-T6 specimens which was attributed to the longer pressure duration of the shot peening process which results in greater plastic deformation. It was also shown that polishing the shot peened and laser shock peened specimens after their respective peening procedures resulted in a significant increase in fatigue life. Polishing after peening resulted in a 3.4× fatigue life increase in the shot peened test specimens (T6 condition) and a 5.4× fatigue life increase in the laser shock peened test specimens (T6 condition). This result highlights the role that surface roughness plays in component fatigue life. Furthermore, the increase in the average fatigue life of the polished test specimens shows that the depth of the residual compressive stresses induced by the peening processes were deep enough to allow for surfaces layers to be removed from the test specimens without any detrimental effect to the overall average fatigue life of the components. The result also suggests that the magnitudes of the residual stresses induced by the laser shock peening process being greater than those of the shot peening process. The main difference between the peening treatments was demonstrated as originating from the surface roughening effects of the two peening procedures. The laser shock peening process only slightly increased the surface roughness of a polished AA7075-T6 test specimens. The shot peening process severely affected the surface roughness of the test specimens, creating many potential crack initiation sites. The AA7075-O test specimens (annealed) showed no overall improvement in their fatigue life, regardless of the mechanical treatment received. The increased ductility of the specimens during the 3-point bending fatigue process led to stress relieving of the peening induced compressive stresses. The specimens were however still fatigued to failure. This enabled the analysis of the effect of the peening induced surface roughness to be analysed. It was found that the shot peened and laser shock peened surface roughness values were significantly higher than the roughness values of the T6 specimens owing to the increased ductility and thus workability of the test specimens. These increased surface roughnesses resulted in the shot peened test specimens failing before the laser shock peened specimens. Both sets of peened specimens failed before the "as machined" and polished test specimens highlighting the role that their induced surface roughnesses had on their fatigue lives. The cross-sectional microstructures of the peened samples in each material condition showed varied changes in the microstructure of the treated aluminium alloy. There was evidence of a large degree of plastic deformation near the surface of shot peened specimens in both material conditions. However, there was limited evidence of changes to the grains structure of the laser shock peened specimens, in both material conditions. In addition, the ability of the laser shock peening process to recover fatigue life in damaged components was also investigated. This brought into question whether the laser shock peening process can be used on a partially fatigued component at the point of crack initiation, in an attempt to further improve the fatigue life of the component. It was found that the laser shock peening of the cracks initiated in fatigue life recovery process did little to effectively recover fatigue life in the damaged components. A degree of life extension was present as cracks re-initiated after a few thousand cycles and was attributed to crack tip closure. This closure led to a general reduction in the fatigue crack growth rate when compared to laser shock peened/polished test specimens fatigued at the same stress.
APA, Harvard, Vancouver, ISO, and other styles
9

Smyth, Niall. "Effect on fatigue performance of residual stress induced via laser shock peening in mechanically damaged 2024-351 aluminium sheet." Thesis, Cranfield University, 2014. http://dspace.lib.cranfield.ac.uk/handle/1826/9321.

Full text
Abstract:
During manufacture and maintenance the fuselage skin of aircraft are susceptible to damage in the form of scratches. Normally not considered to be of major concern to aircraft structural integrity some airlines discovered fatigue cracks had initiated at the root of scratches. Crack propagation was in the through thickness direction and if left untreated could cause rapid decompression of the passenger cabin. Standard repair methodology requires patches be riveted around scratch damage and in extreme cases could require entire replacement of affected skin panels. Laser shock peening (LSP) is an emerging surface treatment that has been shown to improve fatigue performance of safety critical components by inducing a surface layer of compressive residual stress. In this work LSP was applied along the scratch damage in an effort to restore pristine fatigue performance. The aim of the project was to model the effect on fatigue crack growth rate of residual stress fields induced via LSP and to validate predictions by comparison to experimental test results. The scratches were recreated under controlled laboratory conditions using a diamond tipped tool. This process allowed creation of reproducible V shaped scribes to controlled depth, wall angle and root radius. Scribes of depth 50 and 150 μm with root radius 5 μm were created in dogbone shaped samples of 2 mm thick 2024‐T351 clad aluminium. Samples were tested in fatigue at an R = 0.1 and maximum stress of 200 MPa. The scribe damage reduced fatigue life compared to the pristine material by a factor of 22. Scribed samples were processed using LSP treatment from different providers that created known residual stress fields in the material. The fatigue life of scribed samples after peening varied from a further decrease to a 13 times increase dependent on the residual stress field induced. An elastic‐plastic crack closure based finite element model was created to determine the effect on stress intensity factor and stress ratio of residual stress. Fatigue lives calculated were within a factor of 2 of experimental lives. It was predicted that crack closure was present during up to 80% of the applied load cycle due to the compressive residual stress field. However plasticity induced crack closure actually reduced after peening because the compressive residual stress field induced a smaller plastic zone at the crack tip and hence reduced the plastic wake. A residual stress based fatigue life sensitivity study was performed to optimise the profile of the residual stress field for improved fatigue performance. The required profile was created in test samples using LSP. The fatigue life of peened samples increased by a factor of up to 15 however pristine life was not fully recovered. A restriction imposed by the industrial application was peening applied to one face only. This created an unbalanced stress field that resulted in sample distortion to maintain equilibrium. The distortion induced out of plane bending stresses during testing and caused premature crack initiation on the unpeened face. However using interrupted fatigue tests it was found that although crack initiation also occurred at the root of the scribes the cracks were arrested after 24 μm of propagation. This was consistent with the findings of the crack growth prediction model.
APA, Harvard, Vancouver, ISO, and other styles
10

D'Ermilio, Jessica. "Laser shock peening treatment to control and moderate fatigue crack growth in aircraft structure based on residual stress engineering approach." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amslaurea.unibo.it/6865/.

Full text
Abstract:
Laser Shock Peening (LSP) is a surface enhancement treatment which induces a significant layer of beneficial compressive residual stresses of up to several mm underneath the surface of metal components in order to improve the detrimental effects of the crack growth behavior rate in it. The aim of this thesis is to predict the crack growth behavior in metallic specimens with one or more stripes which define the compressive residual stress area induced by the Laser Shock Peening treatment. The process was applied as crack retardation stripes perpendicular to the crack propagation direction with the object of slowing down the crack when approaching the peened stripes. The finite element method has been applied to simulate the redistribution of stresses in a cracked model when it is subjected to a tension load and to a compressive residual stress field, and to evaluate the Stress Intensity Factor (SIF) in this condition. Finally, the Afgrow software is used to predict the crack growth behavior of the component following the Laser Shock Peening treatment and to detect the improvement in the fatigue life comparing it to the baseline specimen. An educational internship at the “Research & Technologies Germany – Hamburg” department of AIRBUS helped to achieve knowledge and experience to write this thesis. The main tasks of the thesis are the following: •To up to date Literature Survey related to “Laser Shock Peening in Metallic Structures” •To validate the FE model developed against experimental measurements at coupon level •To develop design of crack growth slowdown in Centered Cracked Tension specimens based on residual stress engineering approach using laser peened strip transversal to the crack path •To evaluate the Stress Intensity Factor values for Centered Cracked Tension specimens after the Laser Shock Peening treatment via Finite Element Analysis •To predict the crack growth behavior in Centered Cracked Tension specimens using as input the SIF values evaluated with the FE simulations •To validate the results by means of experimental tests
APA, Harvard, Vancouver, ISO, and other styles

Books on the topic "Shock fatigue"

1

Schneider, Gerold A., and Günter Petzow, eds. Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-8200-1.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

A, Schneider Gerold, Petzow G, North Atlantic Treaty Organization. Scientific Affairs Division., and NATO Advanced Research Workshop on the Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics (1992 : Munich, Germany), eds. Thermal shock and thermal fatigue behavior of advanced ceramics. Dordrecht: Kluwer Academic Publishers, 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
3

Schneider, Gerold A. Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics. Dordrecht: Springer Netherlands, 1993.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
4

Berlin electropolis: Shock, nerves, and German modernity. Berkeley: University of California Press, 2006.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
5

Raman, Ganesh. Screech tones from rectangular jets with spanwise oblique shock-cell structures: [final contractor report]. [Cleveland, Ohio]: National Aeronautics and Space Administration, [Lewis Research Center, 1996.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
6

Zhang, Yongkang. Laser Shock Processing of FCC Metals: Mechanical Properties and Micro-structural Strengthening Mechanism. Berlin, Heidelberg: Springer Berlin Heidelberg, 2013.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
7

Lalanne, Christian. Fatigue Damage. Wiley & Sons, Incorporated, John, 2009.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
8

Lalanne, Christian. Mechanical Vibration and Shock Analysis: Fatigue Damage. Wiley & Sons, Incorporated, John, 2014.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
9

Lalanne, Christi, and Christian Lalanne. Fatigue Damage (Mechanical Vibration and Shock). CRC, 2002.

Find full text
APA, Harvard, Vancouver, ISO, and other styles
10

Lalanne, Christian. Mechanical Vibration and Shock Analysis, Random Vibration. Wiley & Sons, Incorporated, John, 2010.

Find full text
APA, Harvard, Vancouver, ISO, and other styles

Book chapters on the topic "Shock fatigue"

1

Aubier, M. "Respiratory Muscle Fatigue During Cardiogenic Shock." In Update in Intensive Care and Emergency Medicine, 264–67. Berlin, Heidelberg: Springer Berlin Heidelberg, 1985. http://dx.doi.org/10.1007/978-3-642-70309-6_55.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Lalanne, Christian. "Fatigue Damage Spectrum of a Shock." In Specification Development, 165–70. Chichester, UK: John Wiley & Sons, Ltd, 2014. http://dx.doi.org/10.1002/9781118931219.ch5.

Full text
APA, Harvard, Vancouver, ISO, and other styles
3

Fett, T., K. Keller, J. Kübler, and D. Munz. "Thermal Fatigue of Glass." In Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics, 383–92. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-8200-1_32.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Lanone, Sophie, Camille Taillé, Jorge Boczkowski, and Michel Aubier. "Diaphragmatic fatigue during sepsis and septic shock." In Applied Physiology in Intensive Care Medicine, 395–401. Berlin, Heidelberg: Springer Berlin Heidelberg, 2009. http://dx.doi.org/10.1007/978-3-642-01769-8_56.

Full text
APA, Harvard, Vancouver, ISO, and other styles
5

Lanone, Sophie, Camille Taillé, Jorge Boczkowski, and Michel Aubier. "Diaphragmatic fatigue during sepsis and septic shock." In Applied Physiology in Intensive Care Medicine 1, 309–15. Berlin, Heidelberg: Springer Berlin Heidelberg, 2012. http://dx.doi.org/10.1007/978-3-642-28270-6_53.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Mészáros, István, and János Ginsztler. "Magnetic Investigation of Thermal Shock Fatigue Process." In The Mechanical Behavior of Materials X, 1283–86. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-440-5.1283.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

Becher, P. F., and G. Fantozzi. "Summary IV.1. Thermal Shock." In Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics, 365–68. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-8200-1_30.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Kravchuk, L. V. "Thermal Fatigue of Engineering Ceramics." In Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics, 419–28. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-8200-1_35.

Full text
APA, Harvard, Vancouver, ISO, and other styles
9

Bradt, R. C. "Summary IV.2. Thermal Fatigue." In Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics, 443–44. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-8200-1_37.

Full text
APA, Harvard, Vancouver, ISO, and other styles
10

Kirchhoff, G. "Thermal Shock Fracture by Laser Irradiation." In Thermal Shock and Thermal Fatigue Behavior of Advanced Ceramics, 245–51. Dordrecht: Springer Netherlands, 1993. http://dx.doi.org/10.1007/978-94-015-8200-1_20.

Full text
APA, Harvard, Vancouver, ISO, and other styles

Conference papers on the topic "Shock fatigue"

1

Shcherbak, Petr Nikolaevich. "MODELING SHOCK-FATIGUE PROCESSES IN RAILS." In Инновационные технологии в строительстве и управление техническим состоянием инфраструктуры. Ростов-на-Дону: Ростовский государственный университет путей сообщения, 2022. http://dx.doi.org/10.46973/9785907295612_2022_186.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

Clauer, Allan H., and David F. Lahrman. "Laser Shock Peening for Fatigue Resistance." In ASME 2000 International Mechanical Engineering Congress and Exposition. American Society of Mechanical Engineers, 2000. http://dx.doi.org/10.1115/imece2000-2681.

Full text
Abstract:
Abstract Laser shock peening is developing into a commercial surface enhancement process for increasing the fatigue life of metal components. The process produces deep residual compressive stresses into treated surfaces which inhibit the initiation and propagation of fatigue cracks. The process has been particularly effective in increasing the resistance to foreign object damage in fan and compressor blades of aircraft gas turbine engines. However, the potential application of this process is much broader, encompassing automotive, tooling and dies, and others. Significant effort is being made to lower the cost and increase the throughput of the process, to make it an affordable process for many more applications. This describes the process and reviews the progress being made in the technology, both in material property enhancement and use of the process, and towards reducing cost and increasing throughput.
APA, Harvard, Vancouver, ISO, and other styles
3

Fantini, Vincenzo, Laura Serri, and P. Bianchi. "Laser thermal shock and fatigue testing system." In Lasers and Optics in Manufacturing III, edited by Leo H. J. F. Beckmann. SPIE, 1997. http://dx.doi.org/10.1117/12.281114.

Full text
APA, Harvard, Vancouver, ISO, and other styles
4

Segall, A. E., J. R. Hellmann, and R. E. Tressler. "Thermal Shock and Fatigue Behavior of Ceramic Tubes." In ASME 1993 Design Technical Conferences. American Society of Mechanical Engineers, 1993. http://dx.doi.org/10.1115/detc1993-0064.

Full text
Abstract:
Abstract A narrow circumferential helium quench was used to thermally shock and fatigue internally heated alumina, reaction bonded, and sintered alpha silicon carbide tubes at 500°C and 1000°C. During these tests, transient temperature measurements required for thermal and stress-profile calculations were obtained through the use of micro-thermocouples positioned along the internal surface of the tubes. Acoustic emissions were also employed for in situ monitoring of crack initiation and propagation of the resident flaw populations during the single and repeated (up to 5) thermal shocks. Post-quench inspections and destructive burst tests were used to correlate the existence, extent, and statistical (Weibull) nature of the damage induced by the cycling. Results indicated progressive strength degradation in alumina tubes with repeated thermal cycles. In contrast, the thermally-cycled silicon carbide samples either showed no damage at all, or suffered minimal progressive strength degradation after the first cycle. In any case, the complex stress distributions computed from an FEA-based inverse heat transfer analysis were required to understand the observed damage (crack paths) and apparent fatigue behavior.
APA, Harvard, Vancouver, ISO, and other styles
5

Singh, Gulshan, Thomas Spradlin, and Ramana Grandhi. "Fatigue Life Optimization Using Laser Shock Peening Process." In 50th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2009. http://dx.doi.org/10.2514/6.2009-2184.

Full text
APA, Harvard, Vancouver, ISO, and other styles
6

Ouroua, Y., K. Azouaoui, A. Mesbah, N. Ouali, and T. Boukharouba. "Some insights into the impact fatigue damage behaviour in laminated composites." In STRUCTURES UNDER SHOCK AND IMPACT 2006. Southampton, UK: WIT Press, 2006. http://dx.doi.org/10.2495/su060361.

Full text
APA, Harvard, Vancouver, ISO, and other styles
7

"Effects of laser shock peening on fatigue crack behaviour in aged duplex steel specimens." In 19th International Conference on New Trends in Fatigue and Fracture. USACM, 2019. http://dx.doi.org/10.36717/ucm19-8.

Full text
APA, Harvard, Vancouver, ISO, and other styles
8

Urquiaga Valdes, M., R. G. Saint-Jacques, and C. Moreau. "Thermal Shock Resistance of Plasma Sprayed Tungsten Coatings." In ITSC 1997, edited by C. C. Berndt. ASM International, 1997. http://dx.doi.org/10.31399/asm.cp.itsc1997p0055.

Full text
Abstract:
Abstract Plasma sprayed tungsten coatings are considered as potential candidates for materials in contact with the plasma in future fusion reactors. In this work, the thermal shock resistance of these coatings is studied to determine which of five changed deposition parameters most influences the coating's performance. The thermal shocks were generated with a pulsed electron beam gun. The pulse duration was 0.2 and 0.5 s and the absorbed power density 60 MW/m2. Two series of samples were analyzed. One was plasma sprayed at atmospheric pressure (AP) and the other at low pressure (LP). The LP coatings were deposited on a molybdenum alloy (TZM). AP coatings were deposited on molybdenum and on water cooled copper coupons for fatigue tests. The porosity seems to be a positive factor for thermal shock resistance. The thickness of the coatings and the spraying atmosphere were found to strongly influence the thermal shock resistance. In the case of the fatigue test, some coatings withstood up to 1000 shocks of 0.5 s duration.
APA, Harvard, Vancouver, ISO, and other styles
9

Paffumi, Elena, Karl-Fredrik Nilsson, and Nigel Taylor. "Thermal Fatigue Cyclic-Down Shocks on 316L Model Pipe Components." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61853.

Full text
Abstract:
There is a continuing need for reliable thermal fatigue analysis tools to ensure that high safety levels are maintained in the main coolant lines of light water reactors. To advance the accuracy and reliability of thermal fatigue load determination, a combined experimental and numerical investigation has been conducted on cylindrical components of 316L stainless steel subjected to cyclic thermal shocks of varying intensity. Slightly different experimental conditions were applied in each test to explore the effect of ΔTmax values of increasing severity, the effect of a superimposed static axial load and a reduced test piece wall thickness. Particular attention is given in this work to the influence of a constant tensile axial load on the quenching down shock damage. A comparison between thermal down-shock tests with and without additional constant tensile load is analysed in details here below.
APA, Harvard, Vancouver, ISO, and other styles
10

Zou, Shikun, and Ziwen Cao. "The Fatigue Properties of Laser Shock Processed Aluminum Alloy 7050." In ASME 2007 Pressure Vessels and Piping Conference. ASMEDC, 2007. http://dx.doi.org/10.1115/pvp2007-26047.

Full text
Abstract:
In order to develop the application of laser shock processing (also named laser peening or LSP in short) as a strengthening technology for 7050 aluminum alloy fastener holes, the fatigue properties of laser shock-processed aluminum alloy specimens were investigated. At first, the dislocation density and surface residual stress induced in the shock affected zone was characterized and compared with that of the base material. Then, the fatigue specimens with stress-concentration hole (notch) were treated by LSP. The fatigue life of LSP-treated specimens were measured and compared with that of specimens made from base material without LSP. Fatigue tests were taken under special flight spectrum loading condition for mid-airframe. The results indicated that laser peening improved the fatigue life of all specimens tested. Specimens treated by LSP before hole-drilling had longer fatigue life than those specimens treated by LSP after hole-drilling. At last, the difference of both sequences was investigated by analyzing the plastic strain and residual stress induced by LSP. LSP induced both plastic strain and deformation at the surface layer. The plastic strain induced by LSP was shown to produce harmful orifices with sharp-angle near the edge of hole. The residual stress induced by LSP appears to remain compressive even after the hole-drilling process. In average, the fatigue life of specimens treated by LSP before hole-drilling was found to be 173% longer than that of untreated samples and approaching the life enhancement factor demonstrated by rod extrusion method (on specimens with large diameter holes).
APA, Harvard, Vancouver, ISO, and other styles

Reports on the topic "Shock fatigue"

1

Vasudevan, Vijay K., John Jackson, Sebastien Teysseyre, Bogdan Alexandreanu, and Yiren Chen. Investigation of the Use of Laser Shock Peening for Enhancing Fatigue and Stress Corrosion Cracking Resistance of Nuclear Energy Materials. Office of Scientific and Technical Information (OSTI), March 2017. http://dx.doi.org/10.2172/1347705.

Full text
APA, Harvard, Vancouver, ISO, and other styles
2

SOUND RADIATION OF ORTHOTROPIC STEEL DECKS SUBJECTED TO MOVING VEHICLE LOADS. The Hong Kong Institute of Steel Construction, August 2022. http://dx.doi.org/10.18057/icass2020.p.052.

Full text
Abstract:
Orthotropic steel decks (OSDs) are widely used in the construction of steel bridges due to their high bearing capacity and low material consumption. Current investigations into OSDs mainly focus on issues associated with static, stability, fatigue, etc. However, from the perspective of dynamics, structures with low dead loads may be susceptible to excessive vibration and noise, which occurs when shocks caused by moving traffic loads are transferred to the bridge deck and other components. Hence, bridge vibration and the associated noise are critical issues in steel bridges. This paper investigates the vibration and noise characteristics of OSDs under moving vehicle loads by using analytical method. First, the forced vibration response of the OSDs is solved by the Finite Element Method(FEM), and then the obtained response is used as the boundary condition of the OSDs boundary element model to solve the acoustic radiation. Finally, the variation rules of the vibration and sound radiation of the OSDs are analyzed when the load parameters, boundary conditions and structural parameters are changed. The results show that when analyzing the high-frequency vibration and noise of the OSDs, the all-shell-element model should be selected. The high frequency part of vibration and sound pressure of the OSDs is greater than the low frequency part under moving load. Increasing the load speed will increase the low-frequency part of vibration and sound pressure, but increasing the load eccentricity will have the opposite result. Strengthening the boundary constraints and increasing the number of ribs will suppress the vibration and reduce the sound pressure.
APA, Harvard, Vancouver, ISO, and other styles
We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!

To the bibliography