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Relevant bibliographies by topics / Multiaxial fatigue

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Academic literature on the topic 'Multiaxial fatigue'

Author: Grafiati

Published: 4 June 2021

Last updated: 7 July 2024

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Journal articles on the topic "Multiaxial fatigue"

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Ronchei, Camilla, Andrea Carpinteri, Giovanni Fortese, Daniela Scorza, and Sabrina Vantadori. "Fretting High-Cycle Fatigue Assessment through a Multiaxial Critical Plane-Based Criterion in Conjunction with the Taylor’s Point Method." Solid State Phenomena 258 (December 2016): 217–20. http://dx.doi.org/10.4028/www.scientific.net/ssp.258.217.

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The critical plane-based multiaxial criterion originally proposed by the authors for plain fatigue is here applied to estimate the crack initiation life of fretting high-cycle fatigued structural components. Although fretting fatigue can be regarded as a case of multiaxial fatigue, the common multiaxial fatigue criteria have to be modified to account for the severe stress gradients in the contact zone. Therefore, the above criterion is used in conjunction with the Taylor’s point method to numerically estimate the fatigue life of Ti-6Al-4V and Al-4Cu specimens under cylindrical contacts.

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Lu, Chun, Jiliang Mo, Ruixue Sun, Yuanke Wu, and Zhiyong Fan. "Investigation into Multiaxial Character of Thermomechanical Fatigue Damage on High-Speed Railway Brake Disc." Vehicles 3, no. 2 (June 1, 2021): 287–99. http://dx.doi.org/10.3390/vehicles3020018.

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The multiaxial character of high-speed railway brake disc thermomechanical fatigue damage is studied in this work. Although the amplitudes and distributions of temperature, strain and stress are similar with uniform and rotating loading methods, the multiaxial behavior and out-of-phase failure status can only be revealed by the latter one. With the help of a multiaxial fatigue model, fatigue damage evaluation and fatigue life prediction are implemented, the contribution of a uniaxial fatigue parameter, multiaxial fatigue parameter and out-of-phase failure parameter to the total damage is discussed, and it is found that using the amplitude and distribution of temperature, stress and strain for fatigue evaluation will lead to an underestimation of brake disc thermomechanical fatigue damage. The results indicate that the brake disc thermomechanical fatigue damage belongs to a type of multiaxial fatigue. Using a uniaxial fatigue parameter causes around 14% underestimation of fatigue damage, while employing a multiaxial fatigue parameter without the consideration of out-of-phase failure will lead to an underestimation of about 5%. This work explains the importance of studying the thermomechanical fatigue damage of the brake disc from the perspective of multiaxial fatigue.

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Shang, De Guang, Guo Qin Sun, Jing Deng, and Chu Liang Yan. "Multiaxial Fatigue Damage Models." Key Engineering Materials 324-325 (November 2006): 747–50. http://dx.doi.org/10.4028/www.scientific.net/kem.324-325.747.

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Two multiaxial damage parameters are proposed in this paper. The proposed fatigue damage parameters do not include any weight constants, which can be used under either multiaxial proportional loading or non-proportional loading. On the basis of the research on the critical plane approach for the tension-torsion thin tubular multiaxial fatigue specimens, two multiaxial fatigue damage models are proposed by combining the maximum shear strain and the normal strain excursion between adjacent turning points of the maximum shear strain on the critical plane. The proposed multiaxial fatigue damage models are used to predict the fatigue lives of the tension-torsion thin tube, and the results show that a good agreement is demonstrated with experimental data.

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Wang, C. H., and M. W. Brown. "Life Prediction Techniques for Variable Amplitude Multiaxial Fatigue—Part 1: Theories." Journal of Engineering Materials and Technology 118, no. 3 (July 1, 1996): 367–70. http://dx.doi.org/10.1115/1.2806821.

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Fatigue life prediction under multiaxis random loading is an extremely complex and intractable topic; only a few methods have been proposed in the literature. In addition, experimental results under multiaxis random loading are also scarce. In part one of this two-part paper, a multiaxial non-proportional cycle counting method and fatigue damage calculation procedure are proposed, which is compared with one published damage-searching method. Both theories are based on critical plane concepts, one being an extension of the local strain approach for uniaxial variable amplitude loading and the other employing a new counting algorithm for multiaxis random loading. In principle, these two methods can be considered as bounding solutions for fatigue damage accumulation under multiaxis random loading.

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Liu, Jianhui, Xin Lv, Yaobing Wei, Xuemei Pan, Yifan Jin, and Youliang Wang. "A novel model for low-cycle multiaxial fatigue life prediction based on the critical plane-damage parameter." Science Progress 103, no. 3 (July 2020): 003685042093622. http://dx.doi.org/10.1177/0036850420936220.

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Multiaxial fatigue of the components is a very complex behavior. This analyzes the multiaxial fatigue failure mechanism, reviews and compares the advantages and disadvantages of the classic model. The fatigue failure mechanism and fatigue life under multiaxial loading are derived through theoretical analysis and formulas, and finally verified with the results of multiaxial fatigue tests. The model of multiaxial fatigue life for low-cycle fatigue life prediction model not only improves the prediction accuracy of the classic model, but also considers the effects of non-proportional additional hardening phenomena and fatigue failure modes. The model is proved to be effective in low-cycle fatigue life prediction under different loading paths and types for different materials. Compared with the other three classical models, the proposed model has higher life prediction accuracy and good engineering applicability.

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Yin, Xiang, De-Guang Shang, Gang Zhang, Dao-Hang Li, Hang Zhang, Cheng Qian, Shuai Zhou, and Guo-Cheng Hao. "Thermal-mechanical fatigue life prediction considering fatigue-creep interaction effects." Journal of Physics: Conference Series 2569, no. 1 (August 1, 2023): 012074. http://dx.doi.org/10.1088/1742-6596/2569/1/012074.

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Abstract This study proposed a multiaxial variable temperature and amplitude damage assessment model to predict the variable temperature and amplitude fatigue life of high-temperature alloys, which are often subjected to varying multiaxial mechanical and temperature loads. To validate the proposed model, seven variable temperature and amplitude fatigue tests were conducted on GH4169 nickel-based high-temperature alloy. The proposed model shows good accuracy and reliability in predicting the lifetime of high-temperature alloy components under multiaxial mechanical and temperature loads.

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Wang, Lei, Wu Zhen Li, and Tian Zhong Sui. "Review of Multiaxial Fatigue Life Prediction Technology under Complex Loading." Advanced Materials Research 118-120 (June 2010): 283–88. http://dx.doi.org/10.4028/www.scientific.net/amr.118-120.283.

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The research on multiaxial fatigue life prediction methods is reviewed in the present paper from two aspects of experiment and theory. It is pointed out that the reasonable methods of the critical plane determining, multiaxial cycle counting and multiaxial fatigue damage parameter fixing are necessary if the fatigue life prediction models established under the multiaxial constant amplitude loading were applied to the life prediction of the complex multiaxial load. The shortcomings of existing researches are discussed. In the aspect of experiment, it is devoid of the multiaxial fatigue test that the loading components acted with different frequencies, and in the aspect of theory, the additional hardening effect of the multiaxial out-of-frequency loading is not considered. Both in the theoretical research and practical engineering applications, the problem of the out-of-frequency multiaxial loading is a pressing issue.

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Zhao, Er Nian, and Wei Lian Qu. "Multiaxial Fatigue Life Prediction of Metallic Materials Based on Critical Plane Method under Non-Proportional Loading." Key Engineering Materials 730 (February 2017): 516–20. http://dx.doi.org/10.4028/www.scientific.net/kem.730.516.

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The critical plane method is widely discussed because of its effectiveness for predicting the multiaxial fatigue life prediction of metallic materials under the non-proportional loading conditions. The aim of the present paper is to give a comparison of the applicability of the critical plane methods on multiaxial fatigue life prediction. A total of 205 multiaxial fatigue test data of nine kinds of metallic materials under various strain paths are adopted for the experimental verification. Results shows that the von Mises effective strain parameter and KBM critical plane parameter can give well predicted fatigue lives for multiaxial proportional loading conditions, but give poor prediction lives evaluation for multiaxial non-proportional loading conditions. However, FS parameter shows better accuracy than the KBM parameter for multiaxial fatigue prediction for both proportional and non-proportional loading conditions.

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Bercelli, Lorenzo, Cédric Doudard, and Sylvain Moyne. "Taking into account the non-proportional loading effect on high cycle fatigue life predictions obtained by invariant-based approaches." MATEC Web of Conferences 300 (2019): 12003. http://dx.doi.org/10.1051/matecconf/201930012003.

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Industrial structures are often subjected to multiaxial fatigue loadings. If the multiple stress signals are not synced the loading is said to be non-proportional. Most of the multiaxial fatigue criteria give highly inaccurate lifetime predictions when used in the case of such loadings. The scalar equivalent stress defined by the criteria does not take into account the non-proportional nature of the multiaxial loading and leads to non-conservative predictions. Moreover a multiaxial fatigue criterion can only be applied on a stress cycle which has no clear definition when multiple unsynced signals are to be considered. This study addresses these issues by proposing a correction of an invariant based multiaxial fatigue criterion through the definition of a non-proportional degree indicator. A definition of multiaxial cycle is also given based on the Wang-Brown method. Finally a complete chain of invariant based lifetime prediction for non-proportional multiaxial fatigue is validated.

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Poisson, J. L., S. Méo, F. Lacroix, G. Berton, and N. Ranganathan. "MULTIAXIAL FATIGUE CRITERIA APPLIED TO A POLYCHLOROPRENE RUBBER." Rubber Chemistry and Technology 85, no. 1 (March 1, 2012): 80–91. http://dx.doi.org/10.5254/1.3672431.

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Abstract Due to their interesting mechanical behavior and their diversity, rubber materials are more and more used in industry. Indeed, formulating a multiaxial fatigue criterion to predict fatigue lives of rubber components constitutes an important objective to conceive rubber products. An experimental campaign is developed here to study the multiaxial fatigue behavior of polychloroprene rubber. To reproduce multiaxial solicitations, combined tension–torsion tests were carried out on a dumbbell-type specimen (an axisymmetric rubber part bonded to metal parts with a reduced section at mid-height), with several values of phase angles between tension and torsion. A constitutive model is needed to calculate multiaxial fatigue criteria, and then analyze fatigue results. A large strain viscoelastic model, based on the tension–torsion kinematics, is then used to determine the material's stress–strain law. Dissipated energy density is introduced as a multiaxial fatigue criterion, and compared with those usually used in the literature. A multiaxial Haigh diagram is then built to observe the influence of Rd-ratio (ratio of the axial displacement's minimum to the axial displacement's maximum) on the multiaxial fatigue lives of polychloroprene rubber.

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Dissertations / Theses on the topic "Multiaxial fatigue"

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Liu, Mu-Hsin. "Multiaxial Fatigue Testing Machine." Ohio University / OhioLINK, 2002. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1266241731.

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Swalla, Dana Ray. "Fretting fatigue damage prediction using multiaxial fatigue criteria." Thesis, Georgia Institute of Technology, 1999. http://hdl.handle.net/1853/17033.

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Warneboldt, Iona. "Multiaxial fatigue design of elastomeric parts using Equivalent Fatigue Loads." Electronic Thesis or Diss., Brest, École nationale supérieure de techniques avancées Bretagne, 2022. http://www.theses.fr/2022ENTA0002.

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Trois étapes sont mises en oeuvre ici : la méthode de localisation, la fonction de dommage matériau et le processus de détermination des chargements équivalents en fatigue (CEF). De nombreux essais de fatigue ont été réalisés (415 au total) pour étudier le comportement en fatigue sous chargement multiaxial relaxant et non relaxant sur des éprouvettes de caoutchouc naturel. La durée de vie et les caractéristiques des fissures sont analysées pour finalement introduire un critère de fatigue approprié basé sur le plan critique et permettant de rendre compte de l'effet de déformation moyenne. Ce critère est généralisé à travers une méthode originale de recherche du plan critique. Pour estimer la réponse mécanique locale (méthode de localisation), une méthode de couplage des axes adaptée à la nature non linéaire des structures élastomères est proposée. Elle est basée sur la décomposition multiplicative des tenseurs du gradient de la déformation. Ces deux étapes sont ensuite mises en oeuvre dans le cadre du processus de détermination du CEF. Pour cela, une méthode d'optimisation globale est ajoutée pour déterminer les chargements simplifiés, induisant partout localement le même endommagement en fatigue dans la structure étudiée que le RLD. Le temps de calcul de cette optimisation est réduit en ne considérant qu'un sous-ensemble de points matériels, les plus endommagés, pour la détermination du CEF. Enfin, la méthode a été testée sur une éprouvette afin de souligner ses capacités et de valider l'approche
This thesis introduces an Equivalent Fatigue Load (EFL) approach for the multiaxial fatigue design of elastomeric parts. As direct Finite Element Analysis (FEA) calculations of automotive in-service loads (Road Load Data (RLD)) are too expensive, the objective is to derive simplified load blocks as a realistic input for numerical damage calculations. Three streps are applied for this method: the localization method, the material damage function and the EFL determination process. Various fatigue tests have been conducted (415 samples) to study the fatigue behavior of this complex type of relaxing and non-relaxing multiaxial loading on natural rubber specimens. Lifetime and crack features are analyzed to eventually introduce an appropriate critical planebased fatigue measure and to establish a novel mean strain effect model. This criterion is generalized throughout an original critical plane search method. To estimate the local mechanical response (localization method), this thesis identifies an axes-coupling method that is fitted for the nonlinear nature of elastomeric structures. It is based on the multiplicative decomposition of the deformation gradient tensors. These two steps are then implemented in the framework of the EFLdetermination process. For this, a global optimization method is added to determine the simplified load blocks, causing locally the same fatigue behavior in the given structure. The computational costs of this optimization are reduced by only considering a subset of the most damaged material points for EFLdetermination. Finally, the method has been challenged on a specimen to outline its capabilities and to validate the approach

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Hallett, Joseph F. "Multiaxial strength and fatigue of rubber compounds." Thesis, Loughborough University, 1997. https://dspace.lboro.ac.uk/2134/6759.

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Despite real applications having complex triaxial loading, current physical test methods to predict component behaviour are mainly uniaxial. But previous work has indicated that there may be substantial differences between the rubber's uniaxial and biaxial behaviour and hence through incompressibility, its triaxial properties. In order to quantify these differences equipment was developed to assess the biaxial performance of selected rubber compounds using inflated circular diaphragms. Although allowing higher extensions than stretching a sheet in its own plane, such tests do not allow stress and strain to be measured directly, requiring careful marking of the sample, or calculation through simulation. On the grounds of perceived accuracy, the latter was chosen, requiring accurate, general, elastic constants to high extensions. In this thesis the development of this apparatus, along with the associated techniques is described, along with the development of a new elastic theory. The tests on this new apparatus indicated significant differences between the uniaxial and biaxial strength and fatigue of rubber. In a unimdal test natural rubber (NR) is much stronger than styrene butadiene rubber (SBR) below 35pphr of carbon black. In a biaxial test though the converse is true, although there is some evidence of crystallinity in NR during the biaxial test. Distinct differences were also found in fatigue between the two load cases. When plotted against extension ratio the biaxial life of SBR was found to increase, while the converse is true for NR. However if life is plotted against a function of strain energy, the biaxial life of both polymers increases for a given energy.

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FEIFERIS, ANDRE DOS REIS. "STRUCTURAL EVALUATION OF CRANKSHAFT UNDER MULTIAXIAL FATIGUE." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2018. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=35967@1.

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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO
COORDENAÇÃO DE APERFEIÇOAMENTO DO PESSOAL DE ENSINO SUPERIOR
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTS. DE ENSINO
PROGRAMA DE SUPORTE À PÓS-GRADUAÇÃO DE INSTITUIÇÕES COMUNITÁRIAS DE ENSINO PARTICULARES
Eixos de virabrequim estão sujeitos a carregamentos multiaxiais quando em serviço. Por se tratar de um estado complexo de tensões, os modelos aplicados na determinação da vida em fadiga de tais componentes devem permitir, também, uma abordagem multiaxial, mais avançados do que aqueles adotados para carregamentos uniaxiais. O objetivo deste trabalho foi prever a falha em serviço de eixos virabrequins de unidades geradoras Diesel ou gás de plantas termoelétricas. Falhas recentemente ocorridas em eixos virabrequins no parque termoelétrico nacional justificam o presente estudo, para garantir eficiência e segurança nas operações industriais. Com base no método de elementos finitos, foram calculadas as tensões atuantes em um eixo virabrequim de unidade geradora a gás, com 10 mancais, duas bielas por mancal e fabricado com aço estrutural DIN 34CrNiMo6. Em sequência, adotando-se estas tensões atuantes calculadas, foram aplicados diversos critérios de fadiga para prever sua falha. Para tal, adotaram-se os modelos de Papadopoulos, Findley, Matake, McDiarmid, Carpinteri e Spagnoli, Liu e Mahadevan, Mises, Sines e Crossland, todos de fadiga de alto ciclo, baseados no plano crítico ou na tensão de von Mises. Propriedades de resistência à fadiga do material foram retiradas da literatura. Os resultados obtidos indicaram que o componente é seguro quando avaliado usando tais critérios.
Crankshaft axles are subject to multiaxial loading when in service. Because the resulting state of stresses is complex, models applied to determining the fatigue life of such components employ a multiaxial approach as well, more advanced than those adopted for uniaxial loads. The objective of this work is to predict the failure in service of crankshafts of diesel or gas generating units of thermoelectric plants. Crankshafts reported recent failures in the national thermoelectric power plant justifies the present study, to guarantee efficiency and safety in such industrial operations. Based on the finite element method, the resulting stresses on a DIN 34CrNiMo6 structural steel gas generating unit crankshaft, with 10 bearings, two connecting rods per bearing were calculated. Using these finite element calculated stresses, several fatigue criteria were applied to predict this cranckshaft structural failure. Models due to Papadopoulos, Findley, Matake, McDiarmid, Carpinteri and Spagnoli, Liu and Mahadevan, Mises, Sines and Crossland, all of high cycle fatigue based on the critical plane or von Mises strain, were adopted. Material fatigue properties used in the analyses were compiled from specidized literature. Obtained results indicated that the component considered is safe regarding fatigue loadings, as evaluated using such criteria.

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Bold, P. E. "Multiaxial fatigue crack growth in rail steel." Thesis, University of Sheffield, 1990. http://etheses.whiterose.ac.uk/14807/.

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In the introduction to a recent symposium on rolling contact fatigue, R.A.Smith stated that it was difficult to apply our greatly increased understanding of metal fatigue, to rolling contact fatigue, because of "the apparent lack of alternating tensile stresses to drive the cracks." He went on to say "alternating shear stresses are easily found, but the reproduction of continuous crack growth controlled by shear (Mode II in fracture mechanics terms), has proved to be near impossible." This project has demonstrated that under specific conditions this mode of growth does occur. The project began by studying rolling contact fatigue defects, in particular the 'squat' defect in railway lines, and the stress analyses that have been performed on them. It was concluded that the largest stress cycle experienced by the cracks must be a shear stress. It. series of tests were then performed that loaded a crack in pure shear, or a mixture of tension and shear, looking at the effects of using fully reversed shear loading, and the effects of applying tensile mean stresses to reduce the friction on the crack flanks. However these tests all produced less than one millimetre of mode II growth, before the cracks arrested or branched. The final series of tests however applied a tensile load cycle before each shear load cycle. This time coplanar growth was produced, that is the crack grew in the direction of the maximum shear stress. This type of load cycle is a simplification of the load cycle calculated by Bower and Johnson of Cambridge University, where the tensile load is produced by fluid trapped in the crack. Two crack growth rate formulae were produced that fitted the data, indicating that the growth rate was dependent on both the tensile and the shear parts of the cycle.

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Ninic, Dejan Mechanical &amp Manufacturing Engineering Faculty of Engineering UNSW. "Fatigue in automatic transmissions." Awarded by:University of New South Wales. School of Mechanical and Manufacturing Engineering, 2006. http://handle.unsw.edu.au/1959.4/28056.

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A novel method of predicting the multiaxial high-cycle fatigue strength of metallic components is proposed and verified for various steel, aluminium and cast iron alloys. The proposed Fatigue Damage Function shows superior multiaxial fatigue strength prediction compared to the established methods of Gough and Pollard, McDiarmid and Carpinteri and Spagnoli. A new material property, the Normal Stress Sensitivity Factor, is also introduced and its applicability is verified according to published test results of sixteen different structural alloys. To highlight the effectiveness of the proposed criterion, for industrial applications, a case study has been conducted on heat-treated and not heat-treated automatic transmission output shafts.

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Juneja, Lokesh Kumar. "Multiaxial fatigue damage model for random amplitude loading histories." Thesis, Virginia Tech, 1992. http://hdl.handle.net/10919/41522.

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In spite of many multiaxial fatigue life prediction methods proposed over decades of research, no universally accepted approach yet exists. A multiaxial fatigue damage model developed for approximately proportional random amplitude loading is proposed in this study. A normal strain based analysis incorporating the multiaxial state of stress is conducted along a critical orientation assuming a constant strain ratio. The dominant deformation direction is chosen to be the critical orientation which is selected with the help of a principal strain histogram generated from the given multiaxial loading history. The uniaxial cyclic stress-strain curve is modified for the biaxial state of stress present along the critical orientation for the plane stress conditions. Modified versions of Morrow's and of Smith, Watson, and Topper's (SWT) mean-stress models are used to incorporate mean stresses. A maximum shear strain based analysis is, in addition, conducted to check for the shear dominant fatigue crack growth possibility along the critical direction. The most damaging maximum shear strain is chosen after analyzing the in-plane and the two out-of-plane shear strains.

The minimum of the two life values obtained from SWT model and the shear strain model is compared with the life estimated by the proposed model with the modified Morrow's mean stress model. The former is essentially the life predicted by Socie. The results of the proposed model, as reduced to the uniaxial case, are also compared with the experimental data obtained by conducting one-channel random amplitude loading history experiments.
Master of Science

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Sharifimehr, Shahriar. "Multiaxial Fatigue Analysis under Complex Non-proportional Loading Conditions." University of Toledo / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1544787705876488.

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Carraro, Paolo Andrea. "Multiaxial fatigue behaviour of composite materials: characterisation and modelling." Doctoral thesis, Università degli studi di Padova, 2014. http://hdl.handle.net/11577/3423782.

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Thanks to their lightness and versatility combined with excellent mechanical properties, composite materials underwent an increasing relevance in the last twenty years in many industrial fields, also for structural applications. This class of materials offer a wide range of advantages but it is still characterized by a quite high cost with respect to more traditional structural materials. One of the reasons is the lack of reliable design procedures, as well as of extensive experimental investigations in the literature providing clear and general information. This is particularly evident with reference to the behaviour of composite laminates and bonded joints under multiaxial fatigue loading, which often characterise in-service conditions. With the aim to acquire information on the multiaxial fatigue behaviour of unidirectional composites, a specimen configuration was first defined, suitable to characterise the matrix-dominated multiaxial fatigue behaviour of a composite lamina, which is of great importance for the damage evolution in laminates (chapter 2). Tubular specimens subjected to combined tension/torsion loading were identified as the best compromise between reliability of results, easiness of testing and possibility to obtain multiaxial stress states of interest. In the third chapter the results of an extensive experimental investigation on tubular specimens is presented. Tubes were fatigue tested with several values of the biaxiality (shear to transverse) ratio and load ratio (ratio between the minimum and the maximum fatigue loads). A strong influence of both parameters was found on the off-axis crack initiation and propagation phenomena, as well as on the damage mechanisms at the micro-scale. Uniaxial fatigue tests were then carried out on multidirectional flat laminates, designed to achieve local multiaxial stress states similar to those applied to the tubes by means of tension/torsion external loads. This activity, presented in the fourth chapter, revealed the equivalence between external (obtained by applying external loads in different directions) and internal (due to material anisotropy) multiaxial stress states. This represents a fundamental step for the extension of experimental results and predictive models to general loading conditions. The experimental activity on tubes provided information on the damage mechanisms at the micro-scale, responsible for fatigue failure of a unidirectional lamina. On the basis of these mechanisms a criterion for predicting crack initiation in a unidirectional lamina under multiaxial fatigue was developed by means of a multiscale approach (chapter 5). This criterion resulted in sound agreement with the new data on tubes, with data on flat unidirectional laminates from the literature and with crack initiation data on the off-axis layers of the laminates reported in chapter 4. A basic topic related to the analysis of multidirectional laminates is the stiffness degradation due to off-axis cracks in their plies. Dealing with such a topic, an analytical model was developed for predicting the stiffness of a laminate as a function of the crack density in its layers accounting for the interaction between cracks in different layers (chapter 6). In addition the model is capable of calculating the stress re-distribution due to the presence of cracks. This is fundamental for the development of a new procedure for predicting the fatigue crack density evolution in multidirectional laminates, presented in chapter 7. To this aim the experimental observations, the analytical models and criteria previously presented, combined with a statistical approach, have been used to predict the initiation and propagation of multiple cracks in a laminate. As a consequence, when this procedure is combined with the model presented in chapter 6, both the stiffness degradation and the stress re-distribution, useful for the estimation of the total fatigue life, can be predicted. When composite laminates are used as adherends in bonded joints the bonding surface represents a critical position for the onset of fatigue cracks. As a consequence an experimental investigation on the propagation of a bondline crack in composite bonded joints subjected to mixed mode I + II (opening + sliding) fatigue loading was carried out and presented in chapter 8. A criterion to predict the crack propagation rate under mixed mode loading was also developed, based on the damage mechanisms observed during the experimental campaign. Eventually, in Appendix A an analytical model for predicting the initiation of a fibre-matrix debond crack under biaxial static loads is presented. The model provides useful information on the influence of the main geometrical and interface parameters of the fibre-matrix interface strength.
Grazie alla loro leggerezza e versatilità combinate ad eccellenti proprietà meccaniche, i materiali compositi hanno acquisito un'importanza sempre maggiore negli ultimi vent'anni in molti settori industriali, anche per applicazioni strutturali. A fronte dei numerosi vantaggi offerti da questa classe di materiali vi è un costo che rimane ancora piuttosto elevato rispetto ai più tradizionali materiali da costruzione. Una delle ragioni è la mancanza di procedure di progettazione affidabili e riconosciute, nonché l'assenza, in letteratura, di estese caratterizzazioni sperimentali da cui acquisire informazioni di carattere generale. Ciò è particolarmente evidente in riferimento al comportamento a fatica multiassiale di lamine, laminati e giunzioni incollate in composito. Al fine di sopperire alla mancanza di informazioni sul comportamento a fatica multiassiale di lamine unidirezionali, nonché all'assenza di una procedura adeguata di test, è stata inizialmente definita una configurazione di provini adatta a caratterizzare la risposta matrix-dominated (particolarmente significativa per il danneggiamento a fatica di laminati) di materiali compositi unidirezionali (capitolo 2). Provini tubolari soggetti a carichi ciclici di trazione e torsione combinati sono stati identificati come il miglior compromesso tra affidabilità dei risultati, semplicità di testing e possibilità di ottenere condizioni multiassiali di interesse. Nel terzo capitolo sono riportati i risultati di un'estesa campagna sperimentale su tali provini tubolari in presenza di diversi rapporti di biassialità (tensione di taglio su tensione trasversale) e rapporti di ciclo (rapporto tra il minimo e il massimo carico di fatica). É stata riscontrata una notevole influenza di tali parametri sull'innesco e propagazione di cricche off-axis, nonché sui meccanismi di danneggiamento su scala microscopica. Sono poi stati testati a fatica uni-assiale dei laminai piani multi-direzionali progettati per avere condizioni di multiassialità locali simili a quelle ottenute sui provini tubolari tramite carichi esterni in diverse direzioni. L'attività, presentata al quarto capitolo, ha permesso di verificare l'equivalenza tra condizioni multiassiali ti tipo esterno (carichi in più direzioni) e interno (dovute all'anisotropia di lamine e laminati in composito). Ciò rappresenta uno step fondamentale per l'estensione di risultati sperimentali e modelli previsionali a condizioni di carico generiche. L'attività sperimentale sviluppata sui tubi ha fornito informazioni sui meccanismi di danneggiamento a livello microscopico che sono responsabili del cedimento a fatica della lamina unidirezionale. Sulla base di tali meccanismi è stato proposto un criterio per l'innesco di cricche a fatica multiassiale in lamine in composito basato su un approccio multiscala (capitolo 5). Il criterio è risultato in ottimo accordo con i nuovi dati sperimentali sui campioni tubolari, con dati disponibili in letteratura riguardanti lamine unidirezionali piane e con i dati ad innesco sugli strati off-axis dei laminati testati al capitolo 4. Parlando quindi di laminati multi-direzionali, un aspetto fondamentale è la diminuzione di rigidezza di questi ultimi dovuto all'innesco e propagazione di cricche multiple negli strati off-axis. A tal proposito è stato proposto un modello analitico in grado di legare la densità di cricche in ciascuno strato di un laminato alla diminuzione di rigidezza globale considerando anche l'interazione tra cricche presenti su strati diversi (capitolo 6). Tale modello fornisce anche le distribuzioni di tensione dovute alla presenza delle cricche stesse. Questo è un aspetto di fondamentale importanza per lo sviluppo di una procedura per prevedere l'evoluzione della densità di cricche in laminati multi-direzionali sollecitati a fatica, presentata al capitolo 7. A tale scopo le osservazioni sperimentali, i modelli analitici e i criteri sviluppati in precedenza, combinati ad un approccio di tipo statistico, vengono utilizzati per prevedere l'innesco e propagazione di cricche multiple in un laminato. Di conseguenza, combinata con il modello precedentemente illustrato, la procedura consente di prevedere sia la diminuzione di rigidezza di laminati sia la ridistribuzione delle tensioni per effetto del danneggiamento rappresentando quindi uno strumento utile anche alla stima della vita a fatica totale di un laminato. Quando i laminati in composito sono utilizzati come aderendi in giunzioni incollate, l'interfaccia di incollaggio rappresenta una zona particolarmente critica per l'innesco di cricche a fatica. Di conseguenza è stata analizzata sperimentalmente la propagazione di cricche in giunzioni incollate soggette a carichi ciclici di modo misto I + II (apertura + scorrimento). Ancora una volta i meccanismi osservati su scala microscopica sono stati utilizzati per la formulazione di un criterio damage-based per la previsione della velocità di propagazione di cricche in giunzioni incollate sollecitate in modo misto (capitolo 8). In fine, in Appendice A è presentato un modello analitico sviluppato per la previsione dell'innesco di una cricca di debonding tra fibra e matrice in condizioni di carico statico biassiale. Il modello è utile per trarre informazioni sull'influenza dei principali parametri geometrici e interfacciali sulla resistenza dell'interfaccia fibra-matrice.

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Books on the topic "Multiaxial fatigue"

1

Socie, Darrell. Multiaxial Fatigue. Warrendale, PA: SAE International, 1999. http://dx.doi.org/10.4271/r-234.

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Miller, KJ, and MW Brown, eds. Multiaxial Fatigue. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 1985. http://dx.doi.org/10.1520/stp853-eb.

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International Conference on Biaxial/Multiaxial Fatigue (4th 1994 Saint-Germain en Laye, France). Multiaxial fatigue and design. London: Mechanical Engineering, 1996.

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McDowell, DL, and JR Ellis, eds. Advances in Multiaxial Fatigue. 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959: ASTM International, 1993. http://dx.doi.org/10.1520/stp1191-eb.

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International Conference on Biaxial/Multiaxial Fatigue (2nd 1985 University of Sheffield). Biaxial and multiaxial fatigue. London: Mechanical Engineering Publications, 1989.

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1956-, McDowell David L., and Ellis Rod 1939-, eds. Advances in multiaxial fatigue. Philadelphia, PA: ASTM, 1993.

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1947-, Brown M. W., and Miller K. J, eds. Biaxial and multiaxial fatigue. London: Mechanical Engineering, 1988.

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Ewald, Macha, Będkowski W, Łagoda T, and European Structural Integrity Society, eds. Multiaxial fatigue and fracture. Kidlington, Oxford: Elsevier, 1999.

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J, Miller K., Brown M. W. 1947-, ASTM Committee E-9 on Fatigue., and ASTM Committee E-24 on Fracture Testing., eds. Multiaxial fatigue: A symposium. Philadelphia, Pa: American Society for Testing and Materials, 1985.

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Andrea, Carpinteri, Freitas Manuel de, Spagnoli Andrea, Instituto Superior Técnico (Lisbon, Portugal), Portugal. Ministério da Ciência e da Tecnologia., and European Structural Integrity Society, eds. Biaxial/multiaxial fatigue and fracture. Amsterdam ; Boston: Elsevier, 2003.

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Book chapters on the topic "Multiaxial fatigue"

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Blétry, Marc, and Georges Cailletaud. "Multiaxial Fatigue." In Fatigue of Materials and Structures, 1–46. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2013. http://dx.doi.org/10.1002/9781118616994.ch1.

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Milella, Pietro Paolo. "Multiaxial Fatigue." In Fatigue and Corrosion in Metals, 477–520. Milano: Springer Milan, 2012. http://dx.doi.org/10.1007/978-88-470-2336-9_9.

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Milella, Pietro Paolo. "Multiaxial Fatigue." In Fatigue and Corrosion in Metals, 593–636. Cham: Springer International Publishing, 2024. http://dx.doi.org/10.1007/978-3-031-51350-3_13.

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Brown, M. W. "Multiaxial Fatigue Failure." In Advances in Fatigue Science and Technology, 339–61. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-2277-8_14.

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Socie, Darrell. "Multiaxial Fatigue Damage Assessment." In Low Cycle Fatigue and Elasto-Plastic Behaviour of Materials, 465–72. Dordrecht: Springer Netherlands, 1987. http://dx.doi.org/10.1007/978-94-009-3459-7_72.

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Shang, De Guang, Guo Qin Sun, Jing Deng, and Chu Liang Yan. "Multiaxial Fatigue Damage Models." In Fracture and Damage Mechanics V, 747–50. Stafa: Trans Tech Publications Ltd., 2006. http://dx.doi.org/10.4028/0-87849-413-8.747.

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Ellyin, Fernand. "Multiaxial Fatigue--A Perspective." In The Mechanical Behavior of Materials X, 205–10. Stafa: Trans Tech Publications Ltd., 2007. http://dx.doi.org/10.4028/0-87849-440-5.205.

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Ellyin, Fernand. "Multiaxial experimental facilities." In Fatigue Damage, Crack Growth and Life Prediction, 179–204. Dordrecht: Springer Netherlands, 1997. http://dx.doi.org/10.1007/978-94-009-1509-1_5.

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Brown, M. W. "Multiaxial Fatigue Crack Propagation Behaviour." In Advances in Fatigue Science and Technology, 363–86. Dordrecht: Springer Netherlands, 1989. http://dx.doi.org/10.1007/978-94-009-2277-8_15.

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Karolczuk, Aleksander, and Ewald Macha. "Critical Planes in Multiaxial Fatigue." In Materials Science Forum, 109–14. Stafa: Trans Tech Publications Ltd., 2005. http://dx.doi.org/10.4028/0-87849-964-4.109.

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Conference papers on the topic "Multiaxial fatigue"

1

Jiang, Yanyao, Tianwen Zhao, Xiaogui Wang, and Zengliang Gao. "Multiaxial Fatigue of 16MnR Steel." In ASME 2006 Pressure Vessels and Piping/ICPVT-11 Conference. ASMEDC, 2006. http://dx.doi.org/10.1115/pvp2006-icpvt-11-93473.

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Uniaxial, torsion, and axial-torsion fatigue experiments were conducted on a pressure vessel steel, 16MnR, at room temperature. The uniaxial experiments were conducted using solid cylindrical specimens. Axial-torsion experiments employed thin-walled tubular specimens subjected to proportional and nonproportional loading. A critical plane multiaxial fatigue criterion recently developed was found to correlate well with all the experiments conducted for the material. In addition, the fatigue criterion correctly predicted the cracking behavior of the material subjected to different loading paths.

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Zhang, Cheng-cheng, Yuan Ren, Jing-yun Gao, Ying Li, and Kun Yang. "Analysis of Multiaxial Fatigue Evaluation in Engine Components Using an Improved Multiaxial Fatigue Life Model." In ASME Turbo Expo 2016: Turbomachinery Technical Conference and Exposition. American Society of Mechanical Engineers, 2016. http://dx.doi.org/10.1115/gt2016-57128.

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Current design methodologies for LCF/HCF of aero engine components are based on traditional uniaxial stress/strain methods like strain-life (ε-N), stress-life (S-N) and Goodman / Haigh diagram approaches, often applied with a wide safe factors to account for uncertainties in the understanding of multiaxial loading and other effects. With constantly striving to improve the performance and life of gas turbine engines, there is a need to increase accuracy of life prediction and reduce maintenance cost. Some multiaxial fatigue methods like Manson-McKnight, Sines, Smith-Watson-Topper etc. were developed to convert the multiaxial stresses into an equivalent uniaxial stress. This conversion simply provides the treatment of both the mean stress, the stress amplitude and directions. However, critical locations in engine components often experience significant multiaxial non-proportional loading conditions, such as blades and LP/HP shafts are subjected to HCF loading associated with mixed bending and torsional vibration modes. In this paper, the use of a new multiaxial fatigue life model was explored in the prediction of multiaxial fatigue behavior in aeronautic materials and structural steel. This new life model is based on the multiaxial S-N curve and an improved multiaxial high-cycle fatigue criterion which validated before by authors. The applied range of this new multiaxial fatigue life model were also compared with other models. Several groups of solid and hollow specimens with different ductile materials were conducted and evaluated under multiaxial loading cases. The predictions based on the proposed model give a better statistical result than other models.

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3

Wei, Haoyang, and Yongming Liu. "Energy-based multiaxial fatigue damage modelling." In 2018 AIAA/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference. Reston, Virginia: American Institute of Aeronautics and Astronautics, 2018. http://dx.doi.org/10.2514/6.2018-0646.

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4

Kurath, Peter. "Multiaxial Fatigue Criteria for Spot Welds." In International Congress & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1992. http://dx.doi.org/10.4271/920668.

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5

Hay, N. C. "Conditioned Spectral Analysis in Multiaxial Fatigue." In International Congress & Exposition. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 1997. http://dx.doi.org/10.4271/970707.

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6

Kazemi, Amir, Zhijun Wu, and Sayed A. Nassar. "Multiaxial Fatigue of Preloaded Threaded Fasteners." In ASME 2015 Pressure Vessels and Piping Conference. American Society of Mechanical Engineers, 2015. http://dx.doi.org/10.1115/pvp2015-45698.

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This experimental study investigates the effect of cyclic multiaxial loading on the High Cycle Fatigue (HCF) life of preloaded threaded fasteners. A special fixture is used for orienting test bolts at different angles relative to the direction of the cyclic load applied by an MTS fatigue testing system. The orientation angle converts the external cyclic load to a combined cyclic axial and shear loading on test bolts. Test data is used for creating the S-N curves for various multiaxial load combinations. The effect of cyclic stress amplitude and mean stress level are investigated.

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7

Liu, Yongming, and Sankaran Mahadevan. "Fatigue Life prediction under multiaxial loading." In 46th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics and Materials Conference. Reston, Virigina: American Institute of Aeronautics and Astronautics, 2005. http://dx.doi.org/10.2514/6.2005-2321.

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8

Curtit, F., A. Le Pecheur, and J. M. Stephan. "Comparison of Fatigue Damage Criteria Applied to Multiaxial Fatigue." In ASME 2008 Pressure Vessels and Piping Conference. ASMEDC, 2008. http://dx.doi.org/10.1115/pvp2008-61735.

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The mixing tees of PWR nuclear power plant are submitted to complex cyclic thermal loadings that could lead to significant fatigue damage as observed on the RHR mixing area of Civaux 1 PWR in 1998. The characteristics of associated mechanical loading have been investigated by both experimental and numerical studies. A constant loading due to mean temperature and pressure is combined with equi-biaxial variable amplitude loading in the field of high cycle fatigue. This paper compares several fatigue damage criteria applied to both low and high cycle fatigue tests on 304 stainless steel specimens under several loading conditions according to mixing zone thermal fatigue loading amplitude. In order to focus the comparison on intrinsic qualities of the models, each criterion is evaluated directly with stress and strain measured on the specimen. The relevance of each criterion for high cycle thermal fatigue is discussed taking into considerations the precision of the results, and also the “usage cost” (including identification and complexity) and the adaptability to cumulative damage rules.

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9

Hotait, M. A., and A. Kahraman. "Estimation of Bending Fatigue Life of Hypoid Gears Using a Multiaxial Fatigue Criterion." In ASME 2013 International Design Engineering Technical Conferences and Computers and Information in Engineering Conference. American Society of Mechanical Engineers, 2013. http://dx.doi.org/10.1115/detc2013-12511.

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In this study, a crack initiation life prediction methodology for the tooth bending fatigue of hypoid gears is proposed. This methodology employs a previously developed finite-element based hypoid gear root stress model [1] of face-milled and face-hobbed hypoid gears to establish the multiaxial stress time histories within the root fillet regions. These stress time histories are combined with a multiaxial crack initiation fatigue criterion to predict life distributions along roots of the pinion and the gear. The predictions of the multiaxial fatigue model are compared to those from a conventional uniaxial fatigue model to establish the necessity for a multiaxial approach. The model is exercised with an example face-milled hypoid gear set from an automotive application to demonstrate the impact of various misalignments as well as the key cutting tool parameters on the resultant tooth bending lives.

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10

Mamiya, Edgar Nobuo, and José Alexander Araújo. "A Criterion to Predict the Fatigue Strength of Hard Metals under Multiaxial Loading." In SAE Brasil International Conference on Fatigue. 400 Commonwealth Drive, Warrendale, PA, United States: SAE International, 2001. http://dx.doi.org/10.4271/2001-01-4065.

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Reports on the topic "Multiaxial fatigue"

1

Beaver, P. W. A Review of Multiaxial Fatigue and Fracture of Fibre-Reinforced Composites. Fort Belvoir, VA: Defense Technical Information Center, January 1987. http://dx.doi.org/10.21236/ada191990.

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2

Riveros, Guillermo, Hussam Mahmoud, and Santiago Lopez. Multiaxial fatigue strength of structural bolts under combined cyclic axial and shear demands. Engineer Research and Development Center (U.S.), July 2019. http://dx.doi.org/10.21079/11681/33270.

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3

Kallmeyer, Alan. Development of a Nonlinear Cumulative Fatigue Damage Methodology for Aircraft Engine Components under Multiaxial Loadings. Fort Belvoir, VA: Defense Technical Information Center, April 2007. http://dx.doi.org/10.21236/ada589686.

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Messner, M. C., and T. L. Sham. Development of a multiaxial deformation measure and creep-fatigue damage summation for multiple load cycle types in support of an improved creep-fatigue design method. Office of Scientific and Technical Information (OSTI), June 2019. http://dx.doi.org/10.2172/1601810.

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Lissenden, Cliff, Tasnin Hassan, and Vijaya Rangari. Monitoring microstructural evolution of alloy 617 with non-linear acoustics for remaining useful life prediction; multiaxial creep-fatigue and creep-ratcheting. Office of Scientific and Technical Information (OSTI), October 2014. http://dx.doi.org/10.2172/1214660.

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Hassan, Tasnim, Cliff Lissenden, and Laura Carroll. Multiaxial Creep-Fatigue and Creep-Ratcheting Failures of Grade 91 and Haynes 230 Alloys Toward Addressing Design Issues of Gen IV Nuclear Power Plants. Office of Scientific and Technical Information (OSTI), April 2015. http://dx.doi.org/10.2172/1178428.

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