Fretting Fatigue Behavior of a Titanium Alloy Ti-6AL-4V at Elevated Temperature PDF Download

Author: Onder Sahan
Publisher:
ISBN: 9781423511564
Category : Titanium-aluminum-vanadium alloys
Languages : en
Pages : 116

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Book Description
The purpose of this research is to investigate the fretting fatigue behavior of the titanium alloy Ti-6Al-4V at elevated temperature is investigated. Fretting and plain fatigue experiments are conducted at 260 . Crack initiation location and crack initiation orientation is measured and fretting and plain fatigue life data of the specimens from these tests are obtained. Fatigue parameters capable of predicting the number of cycles to specimen failure, the crack location and the crack orientation along the contact surface are analyzed. The parameters are calculated by using the computed stresses and strains obtained from the finite element analysis. The mechanisms responsible for the fretting fatigue crack initiation are determined. The effect of elevated temperature is examined by comparing room and elevated temperature fretting and plain fatigue data.

Author: David W. Hoeppner
Publisher: ASTM International
ISBN: 0803128517
Category : Contact mechanics
Languages : en
Pages : 554

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Book Description
This volume includes 36 of the 40 papers presented at the symposium, and a collection of six keynote papers providing background on the subject. Topics covered include parameter effects, environmental effects, crack nucleation, material and microstructural effects, damage analysis, fracture mechanic

Author: Steven E. Kinyon
Publisher: ASTM International
ISBN: 0803134568
Category : Contact mechanics
Languages : en
Pages : 445

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Book Description
Contains 29 contributions drawn from the Third International Symposium on Fretting Fatigue held in Nagaoka, Japan in May 2001. Sections of the volume address fretting wear and crack initiation; fretting fatigue crack and damage; life prediction; fretting fatigue parameter effects; loading condition

Author: Tomasz Liskiewicz
Publisher: Elsevier
ISBN: 0128240970
Category : Technology & Engineering
Languages : en
Pages : 656

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Book Description
Fretting Wear and Fretting Fatigue: Fundamental Principles and Applications takes a combined mechanics and materials approach, providing readers with a fundamental understanding of fretting phenomena, related modeling and experimentation techniques, methods for mitigation, and robust examples of practical applications across an array of engineering disciplines. Sections cover the underpinning theories of fretting wear and fretting fatigue, delve into experimentation and modeling methods, and cover a broad array of applications of fretting fatigue and fretting wear, looking at its impacts in medical implants, suspension ropes, bearings, heating exchangers, electrical connectors, and more. - Covers theoretical fundamentals, modeling and experimentation techniques, and applications of fretting wear and fatigue - Takes a combined mechanics and materials approach - Discusses the differences and similarities between fretting wear and fretting fatigue as well as combined experimental and modeling methods - Covers applications including medical implants, heat exchangers, bearings, automotive components, gas turbines, and more

Author: Lewis C. Lietch
Publisher:
ISBN: 9781423516637
Category : Fretting corrosion
Languages : en
Pages : 129

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Book Description
The fretting fatigue behavior of Ti-6A1-4V was investigated in laboratory air and under a controlled environment consisting of synthetic seawater. Fretting fatigue tests were performed for both low and high cycle fatigue regimes. Finite element analysis was utilized to model and analyze the experimental data. The applied stress range and the Modified Shear Stress Range were evaluated as potential fatigue parameters. The results found from this study can be summarized as: (1) seawater had a deleterious effect on fretting fatigue life in the low cycle fatigue regime but improved life in the high cycle fatigue regime, (2) although the Q/P ratio for both conditions increased with an increasing applied stress, the difference between the two conditions was negligible, (3) debris from dry samples contained titanium and oxides while the debris from seawater samples contained titanium, oxides, and seawater contaminants, (4) fretting scar volume was larger under seawater conditions than dry conditions, (5) there were more, closely spaced striations on the fracture surface of the dry samples than of the seawater samples, and (6) both the applied (far field) stress range and the Modified Shear Stress Range can potentially be used as conservative fretting fatigue parameters under high cycle fatigue conditions.

Author: D.A. Hills
Publisher: Springer Science & Business Media
ISBN: 9401582815
Category : Technology & Engineering
Languages : en
Pages : 251

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Book Description
Failures of many mechanical components in service result from fatigue. The cracks which grow may either originate from some pre-existing macroscopic defect, or, if the component is of high integrity but highly stressed, a region of localized stress concentration. In turn, such concentrators may be caused by some minute defect, such as a tiny inclusion, or inadvertent machining damage. Another source of surface damage which may exist between notionally 'bonded' components is associated with minute relative motion along the interface, brought about usually be cyclic tangential loading. Such fretting damage is quite insidious, and may lead to many kinds of problems such as wear, but it is its influence on the promotion of embryo cracks with which we are concerned here. When the presence of fretting is associated with decreased fatigue performance the effect is known as fretting fatigue. Fretting fatigue is a subject drawing equally on materials science and applied mechanics, but it is the intention in this book to concentrate attention entirely on the latter aspects, in a search for the quantification of the influence of fretting on both crack nucleation and propagation. There have been very few previous texts in this area, and the present volume seeks to cover five principal areas; (a) The modelling of contact problems including partial slip under tangentialloading, which produces the surface damage. (b) The modelling of short cracks by rigorous methods which deal effectively with steep stress gradients, kinking and closure. (c) The experimental simulation of fretting fatigue.

Author: Robert Barry Waterhouse
Publisher: Elsevier Science & Technology
ISBN:
Category : Business & Economics
Languages : en
Pages : 262

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Book Description

Author: David A. Hills
Publisher: Springer
ISBN: 9783030707484
Category : Technology & Engineering
Languages : en
Pages : 226

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Book Description
This book, which has only one very distant forerunner authored by David A. Hills with David Nowell, represents a very big step that is the quantification of these problems and represents the twenty-five years’ worth of work which have gone on at Oxford since the first book on the subject. Fatigue (popularly ‘metal fatigue’) is the primary failure mode of all machines, engines, transmissions and indeed almost all mechanical devices. The propagation of cracks is well understood and is treated in the subject Fracture Mechanics. By contrast, the nucleation of cracks is very hard to quantify and this remains the case with so-called ‘free initiation’ and, to a lesser extent, at cracks nucleated from stress raising features. But the third form of nucleation, where cracks start from the edges of rubbing components, that is, at joints, is potentially a very much better-defined environment, and therefore, the problem is amendable to attack by applied mechanics and experiment. The contents are of value both to those embarking on research on the subject and to practitioner in industry.

Author: Toshio Hattori
Publisher: Springer
ISBN: 9783031464973
Category : Science
Languages : en
Pages : 0

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Book Description
This book provides a comprehensive overview of the mechanical distinctions between fretting damage under axial or bending external forces and fretting damage under a torsional load. It emphasizes the importance of studying practical accident cases to efficiently acquire technical skills. The book is structured around the fundamental technologies of material science, tribology, and mechanics, which are vital for understanding and addressing technical issues. The author has incorporated all fretting countermeasure technologies, which were previously often sensory and empirical in nature, and repositioned them as technologies grounded in fundamental principles. The book proposes an economical approach to product operation that maintains reliability by integrating not only design technology but also maintenance practices. It delves into specific materials, such as titanium alloys and aluminum alloys, which have seen increased use for weight reduction in industries like aerospace. In this book, “Critical Distance Stress Theory” that can easily derive the fatigue limit and fatigue life of the stress singular field at the contact edge was presented. As a result, the fretting fatigue strength and life can be predicted from the same FEM stress analysis as the normal stress concentration part. And finally, introducing a novel fretting mechanical model, the book focuses on scenarios where pressure force (N) and repeated tangential force (F) are applied to two planar objects, with the tangential force being transmitted solely through friction at the contact surface. This model finds relevance in turbine blade connection structures, among other applications. The author references Asai's research example, which encompasses fretting mechanical analysis, fretting wear evaluation, fatigue assessment, and structural damping evaluation using this model.

Author: National Aeronautics and Space Administration (NASA)
Publisher: Createspace Independent Publishing Platform
ISBN: 9781721521548
Category :
Languages : en
Pages : 34

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Book Description
The fatigue behavior (stress-life curve) of gamma titanium aluminide (Ti-48Al-2Cr-2Nb, atomic percent) was examined by conducting two tests: first, a fretting wear test with a fatigue specimen in contact with a typical nickel-based superalloy contact pad in air at temperatures of 296 and 823 K and second, a high-cycle fatigue test of the prefretted Ti-48Al-2Cr-2Nb fatigue specimen at 923 K. Reference high-cycle fatigue tests were also conducted with unfretted Ti-48Al-2Cr-2Nb specimens at 923 K. All Ti-48Al-2Cr-2Nb fatigue specimens were machined from cast slabs. The results indicate that the stress-life results for the fretted Ti-48Al-2Cr-2Nb specimens exhibited a behavior similar to those of the unfretted Ti-48Al-2Cr-2Nb specimens. The values of maximum stress and life for the fretted specimens were almost the same as those for the unfretted specimens. The resultant stress-life curve for the unfretted fatigue specimens was very flat. The flat appearance in the stress-life curve of the unfretted specimens is attributed to the presence of a high density of casting pores. The fatigue strengths of both the fretted and unfretted specimens can be significantly affected by the presence of this porosity, which can decrease the fatigue life of Ti-48Al-2Cr-2Nb. The presence of the porosity made discerning the effect of fretting damage on fatigue strength and life of the specimens difficult. Miyoshi, Kazuhisa and Lerch, Bradley A. and Draper, Susan L. Glenn Research Center NASA/TM-2002-211718, E-13139, NAS 1.15:211718