Download or read book Multiaxial Fatigue Behavior of Additive Manufactured Metals Experiments and Modeling written by Reza Molaei and published by . This book was released on 2019 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Additive manufacturing (AM) technology has gained significant attention in recent years due to several important advantages. However, design of critical load carrying parts using this technique is still at its infancy, partly due to the inferior performance and lack of sufficient understanding of fatigue behavior of AM metals as compared to their wrought counterparts. Similar to most other components in different industries, AM parts typically undergo cyclic loadings through their service life, therefore, fatigue performance is a key performance criterion. In addition, biaxial and multiaxial stresses are common for many components, even under nominal uniaxial loading conditions where the stress state can be multiaxial due to the complexities in the geometry such as notches, or presence of multidirectional residual stresses. Such effects are more pronounced in AM, where geometry complexities result in stress concentrations, multidirectional residual stresses from the fabrication process are inevitable, and produced defects are typically directional resulting in anisotropy. Despite this fact, previous works have only focused on constant amplitude uniaxial fatigue evaluation of AM materials. One of the main advantages of the AM technique is the capability in fabricating complex geometries, in which, as mentioned, stress concentrations might be inevitable. In addition, the rough surface and un-melted particle clusters on the surface of the AM fabricated parts can also act as stress concentrations and significantly affect the fatigue behavior. Therefore, it is essential to be able to accurately characterize and predict the materials behavior in the presence of stress concentrations, such as notches. Regarding to the loading history, service load histories are typically variable amplitude in nature, where the applied stress states may vary with time and, hence, load sequence and their interactions could play an important role in such loadings. This may become more complicated for AM when considering the effect of defects, both internal and surface, and their interaction with the stress concentrations caused by the notches. The effect of such loading for AM metals and processes in terms of cumulative fatigue damage evolution need to be considered, particularly when the stress states are multiaxial. The main objective of this study was to investigate the cyclic and fatigue behaviors of AM metallic alloys under constant and variable amplitude axial, torsion, and combined axial-torsion loadings. This included both unnotched and notched conditions. Two widely used metallic materials in AM were considered for this study. These include Ti-6Al-4V and 17-4 PH stainless steel alloys. Ti-6Al-4V is a high strength, light weight, and high corrosion resistant material with many applications in aerospace and biomedical industries, and 17-4 PH is a Precipitated Hardened (PH) stainless steel with common applications in corrosion resistant applications such as aerospace, petroleum, and chemical industries. The two materials were chosen to get an understanding of the general applicability of the findings for AM metals. Depending on the material, effect of different post-fabrication treatments such as stress relieving and Hot Isostatic Pressing (HIP) methods were evaluated. Surface finish effect was also considered as another key consideration in mechanical behavior evaluation of the AM alloys. To evaluate the build orientation effect, monotonic and fatigue performance of the vertically and diagonally built (at 45) specimens were compared. All of the results from the AM metals were also compared to the fatigue behavior of their conventional wrought metals. Since response of the materials under cyclic loading can vastly differ from their monotonic response due to phenomenon such as cyclic softening or cyclic hardening, both monotonic and cyclic deformation behaviors were studied. Proper fatigue analysis where plastic deformation is present requires characterization of the cyclic deformation behavior. Failure mechanism(s) and cracking behaviors were also carefully examined for all of the materials with different conditions. Knowing these behaviors under cyclic loading is essential to performing accurate fatigue analysis. For the analysis, based on the experimental results, observed microstructures and defect structures, failure mechanisms, and cracking behaviors of the materials with different post treatment conditions, appropriate predictive multiaxial fatigue life prediction models were applied. These include classical equivalent stress- and strain- based analysis approaches as well as more advanced analysis techniques such as critical plane-based damage parameters. For the notched specimen tests, different models, including computational, analytical and empirical approaches were discussed to estimate the local stresses/strains and predict the fatigue lives. However, due to the presence of internal defects in AM materials and their interactions with notches, some of these methods may not be appropriate for AM metals. Therefore, a modification to the Theory of Critical Distance (TCD) was proposed to account for the presence of internal defects in AM metals. In order to evaluate life prediction procedures under variable amplitude multiaxial loading conditions, different aspects were considered to predict the fatigue life. These include studying the effect of defects (both internal and surface), anisotropy, and residual stresses, which may result in different load sequence effects and, therefore, different fatigue life predictions as compared to the conventionally fabricated metals.Using the geometrical freedom offered by additive manufacturing, some novel specimens geometries were also proposed. These included a plate-type specimen geometry for axial fatigue testing, a hollow cylindrical specimen for torsion testing, and two thin-walled circular cross section specimens for torsion or axial-torsion fatigue testing. The proposed geometries reduce the stress concentration at the gage-to-grip transition area, improve the uniformity of the shear stress distribution throughout the wall thickness, and increase buckling resistance during the compression part of the loading cycle..

Download or read book Surface Roughness Effect on Multiaxial Fatigue Behavior of Additive Manufactured Metals and Its Modeling written by Jingzhe Zhang and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Additive manufacturing (AM) has become a very popular topic recently due to its many advantages including short build cycles, convenience of customozation, and most importantly the ability to build components with complex geometry. However, the surface condition of additive manufactured components is not always satisfactory, particularly with respect to fatigue performance. This is because the as-built surface tends to be rough and post surface treatments or processes such as machining and polishing may not be applicable to all AM parts. On the other hand, since many components are under cyclic loading consisting of normal and shear stress, multiaxial fatigue behavior is one of the most important aspects to evaluate. This paper evaluates the surface roughness effect on fatigue behaviors of Ti-6Al-4V allloy samples additively manufactured by laser based powder bed fusion method (L-PBF). Fully reversed axial, torsional, and combined axial-torsion fatigue tests were conducted on specimens with different surface conditions and with different post heat treatments (annealed and HIP). Fatigue life predictions were made using linear elastic fracture mechanic with satisfactory results, as compared to experimental results.

Download or read book Fatigue in Additive Manufactured Metals written by Filippo Berto and published by Elsevier. This book was released on 2023-09-20 with total page 321 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue in Additive Manufactured Metals provides a brief overview of the fundamental mechanics involved in metal fatigue and fracture, assesses the unique properties of additive manufactured metals, and provides an in-depth exploration of how and why fatigue occurs in additive manufactured metals. Additional sections cover solutions for preventing it, best-practice design methods, and more. The book recommends cutting-edge evidence-based approaches for designing longer lasting additive manufactured metals, discusses the latest trends in the field and the various aspects of low cycle fatigue, and looks at both post-treatment and manufacturing process-based solutions. By providing international standards and testing procedures of additive manufactured metal parts and discussing the environmental impacts of additive manufacturing of metals and outlining simulation and modeling scenarios, this book is an ideal resource for users in industry. - Discusses the underlying mechanisms controlling the fatigue behavior of additive manufactured metal components as well as how to improve the fatigue life of these components via both manufacturing processes and post-processing - Studies the variability of properties in additive manufactured metals, the effects of different process conditions on mechanical reliability, probabilistic versus deterministic aspects, and more - Outlines nondestructive failure analysis techniques and highlights the effects of unique microstructural characteristics on fatigue in additive manufactured metals

Download or read book Multiaxial Fatigue written by Darrell Socie and published by SAE International. This book was released on 1999-12-15 with total page 510 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides practicing engineers, researchers, and students with a working knowledge of the fatigue design process and models under multiaxial states of stress and strain. Readers are introduced to the important considerations of multiaxial fatigue that differentiate it from uniaxial fatigue.

Download or read book Mechanical Fatigue of Metals written by José A.F.O. Correia and published by Springer. This book was released on 2019-05-07 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains the proceedings of the XIX International Colloquium on Mechanical Fatigue of Metals, held at the Faculty of Engineering of the University of Porto, Portugal, 5-7 September 2018. This International Colloquium facilitated and encouraged the exchange of knowledge and experiences among the different communities involved in both basic and applied research in the field of the fatigue of metals, looking at the problem of fatigue exploring analytical and numerical simulative approaches. Fatigue damage represents one of the most important types of damage to which structural materials are subjected in normal industrial services that can finally result in a sudden and unexpected abrupt fracture. Since metal alloys are still today the most used materials in designing the majority of components and structures able to carry the highest service loads, the study of the different aspects of metals fatigue attracts permanent attention of scientists, engineers and designers.

Download or read book Multiaxial Notch Fatigue written by Luca Susmel and published by Elsevier. This book was released on 2009-03-20 with total page 589 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal and composite components used in structural engineering not only contain geometrical features resulting in stress concentration phenomena, but they are also subjected to in-service multiaxial fatigue loading. To address the problem, structural engineers need reliable methodologies which allow for an adequate margin of safety. The book summarises methods devised by the author to design real components against multiaxial fatigue by taking full advantage not only of nominal but also of local stress-strain quantities.The book begins by reviewing definitions suitable for calculating the stress-strain quantities commonly used to perform fatigue assessment. The Modified Wöhler Curve Method is then explained in detail, by focusing attention on both the high- and the medium-cycle fatigue regime. The existing links between the multiaxial fatigue criterion and physical properties are also discussed. A procedure suitable for employing the method developed by the author to estimate fatigue damage both in notched and in welded components is explained. The Modified Manson-Coffin Curve method is investigated in depth, by reviewing those concepts playing a fundamental role in the so-called strain based approach. Lastly, the problem of performing the fatigue assessment of composite materials is addressed by considering design parameters influencing composite behaviour under complex cyclic loading paths and those criteria suitable for designing real components against multiaxial fatigue. The book also contains two appendices summarising experimental data from the technical literature. These appendices provide a unique and highly valuable resource for engineers. The appendices summarise around 100 values of the material characteristic length L, experimentally determined by testing specimens made of different engineering materials and about 4500 experimental fatigue results generated by testing plain, notched and welded specimens under constant-amplitude proportional and non-proportional multiaxial fatigue loading are listed. - Summarises methods devised by the author to design real components against multiaxial fatigue - Reviews definitions suitable for calculating the stress-strain quantities commonly used to perform fatigue assessment - Includes an in-depth explanation of both the Modified Wöhler Curve and Modified Manson-Coffin Curve Method

Download or read book Quality Analysis of Additively Manufactured Metals written by Javad Kadkhodapour and published by Elsevier. This book was released on 2022-11-30 with total page 858 pages. Available in PDF, EPUB and Kindle. Book excerpt: Quality Analysis of Additively Manufactured Metals: Simulation Approaches, Processes, and Microstructure Properties provides readers with a firm understanding of the failure and fatigue processes of additively manufactured metals. With a focus on computational methods, the book analyzes the process-microstructure-property relationship of these metals and how it affects their quality while also providing numerical, analytical, and experimental data for material design and investigation optimization. It outlines basic additive manufacturing processes for metals, strategies for modeling the microstructural features of metals and how these features differ based on the manufacturing process, and more.Improvement of additively manufactured metals through predictive simulation methods and microdamage and micro-failure in quasi-static and cyclic loading scenarios are covered, as are topology optimization methods and residual stress analysis techniques. The book concludes with a section featuring case studies looking at additively manufactured metals in automotive, biomedical and aerospace settings. - Provides insights and outlines techniques for analyzing why additively manufactured metals fail and strategies for avoiding those failures - Defines key terms and concepts related to the failure analysis, quality assurance and optimization processes of additively manufactured metals - Includes simulation results, experimental data and case studies

Download or read book Metal Additive Manufacturing Defects Analysis and Prediction of Their Effect on Fatigue Performance written by Niloofar Sanaei and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The technology of additive manufacturing (AM) which is building up parts by joining materials directly informed by 3D model data, is developing rapidly in many industries. It offers advantages such as delivering intricate and complex geometries with the least post processing required. The components made by AM are of interest in biomedical and aerospace applications. AM technologies should produce unique critical parts, such as prosthetics which undergo cyclic loading throughout their service life. Therefore, understanding fatigue behavior of AM metals is one of the most important steps in their part design. In addition, in many applications, the loading condition is multiaxial. Even in parts under uniaxial loading condition, the stress state may still be a combination of axial and shear stress due to complex geometry or interaction of residual stresses and existence of defects. The intrinsic defects of AM metals and the effect of process and post processing parameters on them were investigated in this study. The microstructure and defect content of AM metals and their correlation with fatigue performance were reviewed. The objective was to analyze characteristics of intrinsic AM defects and their variability for various materials, processing and post-processing conditions. The aim was also to evaluate the fatigue behavior of the defective AM metals, develop an appropriate defect sensitive fatigue life prediction framework, and verify the predictions with experimental data. Fracture Mechanics concepts along with phenomenological, empirical, and semi-empirical models such as Murakami's area parameter were applied. Comprehensive defect analysis and fracture surface analysis were performed in 2D by digital microscopy and scanning electron microscopy and in 3D using X-ray computed tomography. Important surface and internal defect characteristics such as size, shape (aspect ratio), location, and orientation, the material microstructure, and the loading and failure mechanism for each batch of specimens were investigated. The key factors were incorporated into fatigue life predictions with appropriate representations. Statistical functions to model the distribution of the defect characteristics, and Extreme Value Statistics (EVS) concepts to compute a prospective maximum defect size were used for fatigue life prediction. Based on the failure analysis, for tensile failure dominated specimens Maximum Principle Stress (MPS) and for shear failure dominated specimens Fatemi-Socie (FS) parameter were used to calculate the stress intensity factor range for defect-based uniaxial and multiaxial fatigue life predictions. The fracture mechanics-based framework could successfully be used for fatigue life prediction of AM metals based on their defect content.

Download or read book Stress intensity Factor Equations for Cracks in Three dimensional Finite Bodies Subjected to Tension and Bending Loads written by J. C. Newman and published by . This book was released on 1984 with total page 98 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Additively Manufactured Metals written by Alexander E. Wilson-Heid and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal additive manufacturing (AM) processes build 3-dimensional (3D) components in a layer-by-layer fashion, which allows for the manufacturing of geometrically complex components that cannot be produced via traditional manufacturing methods, making it an attractive option in many industries. Laser powder bed fusion (L-PBF) AM is a process category of AM that involves using a focused laser to selectively melt and fuse metallic powder to make a component. A common type of defect in AM is lack-of-fusion porosity, where the newly melted powder fails to fully-fuse to the material adjacent or below due to imperfect selection of processing parameters. Understanding the mechanical behavior of material used in AM is important for the safe, reliable, and repeatable application of the technology in industry. This thesis work provides a new understanding of the static uniaxial and multiaxial plasticity and fracture properties of L-PBF Ti-6Al-4V and stainless steel 316L in two material orientations. In particular, a series of experiments over a wide range of stress states that included uniaxial tension, equibiaxial tension, plane strain tension, pure shear, and combined tension/shear were probed to characterize both the plasticity and subsequent failure behavior. Finite element method simulations were used in combination with the experiments to calibrate and validate the stress state dependent, anisotropic plasticity behavior. Fracture behavior of both alloys was found to be stress state dependent in both orientations, and the equivalent plastic strain to failure under the wide range of stress states studied was accurately captured using calibrated ductile fracture criteria, namely the modified Mohr-Coulomb and Hosford-Coulomb models. Hypothesized microstructural driven shear softening in 316L shear dominated experiments was captured in simulations by adopting shear damage criterion in conjunction with the anisotropic plasticity model. Furthermore, this thesis for the first time characterized the effect of penny-shaped defects of varying size on the deformation and failure response of L-PBF 316L under uniaxial tension and three high stress triaxiality stress states. Pores were intentionally introduced using the unique capability of AM to embed enclosed defects at the center of samples. As a result, the 316L material was found to be defect tolerant under uniaxial tension; where the pore did not impact material ductility until the pore was 9% of the sample cross-sectional area. Strain to failure was stress state dependent until a large pore size occupying 4% of the sample cross-sectional area was introduced and then failure became pore size dependent and stress state independent.

Download or read book Multiaxial Fatigue written by Keith John Miller and published by ASTM International. This book was released on 1985 with total page 760 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Multiaxial Fatigue Analysis Under Complex Non proportional Loading Conditions written by Shahriar Sharifimehr and published by . This book was released on 2018 with total page 151 pages. Available in PDF, EPUB and Kindle. Book excerpt: The analysis of the fatigue behavior of metallic materials and components under variable amplitude multiaxial cyclic loading conditions is of great interest to many industries. These loading conditions represent the loading histories to which many parts are subjected throughout their service lives. This type of analysis requires some key steps. These key steps include understanding the deformation behavior of the material including the cyclic behavior under proportional and non-proportional loading conditions, modeling the fatigue behavior of the material under constant amplitude cyclic loading, cycle counting procedures, damage parameters which can represent the damage mechanisms of the material under multiaxial loading conditions, and damage accumulation methods. In this study a methodology for the analysis of fatigue behavior under multiaxial variable amplitude loading conditions is employed which accounts for the aforementioned issues. This methodology consists of several steps of analysis, each of which is developed to address some of the challenges. At its core, the applied methodology uses critical plane analysis based on the failure behavior of each material to assess the fatigue damage under cyclic loading conditions. In order to evaluate the performance of the analysis method, axial, torsional, and combined axial-torsional variable amplitude tests were performed on one ductile and one brittle behaving steel and the experimental results were compared with those estimated from the analysis. The applied methodology resulted in close estimation of fatigue life for both ductile and brittle behaving steels. Furthermore, interactions between different components of stress such as normal and shear stresses play an important role in multiaxial fatigue damage. The main aim of this study was to investigate this interactions effect on fatigue behavior of shear failure mode materials under multiaxial loading conditions. In order to model the influence of normal stress on fatigue damage, the present study introduces a method based on the idea that the normal stress acting on the critical plane orientation causes two types of influence, first by affecting roughness induced closure, and second, by a fluctuating normal stress affecting the growth of small cracks in mode II. The summation of these terms could then be used in shear-based critical plane damage models, for example FS damage model, which use normal stress as a secondary input. In order to investigate the effect of the modification, constant amplitude load paths with different levels of interaction between the normal and shear stresses, as well as variable amplitude tests with histories both taken from service loading conditions, and generated using random numbers were designed for an experimental program. The proposed modification was observed to result in improved fatigue life estimations where significant interactions between normal and shear stresses exist. In addition, since shear fatigue properties are key properties in the analysis of fatigue behavior of ductile metallic materials, this study evaluated the accuracy of different methods in estimating shear fatigue behavior of steels and titanium alloys from properties which are easier to obtain such as monotonic properties and hardness. In order to achieve this goal, test results of 23 types of carbon steel, Inconel 718, and three types of titanium alloys commonly used in industry were found in the literature. In addition, two types of steel and a Ti-6Al-4V titanium alloy were subjected to axial monotonic and fatigue tests as well as torsion fatigue tests. The results of these tests were used along with the data from literature. A reasonable correlation between uniaxial fatigue properties and shear fatigue properties of ductile and brittle behaving materials were found using von Mises and maximum principal strain criteria, respectively. Estimations from the experimentally obtained uniaxial fatigue properties were compared to those from uniaxial fatigue properties which were calculated from the Roessle-Fatemi hardness estimation method. It was observed from the comparison that for steels and Inconel 718 obtaining shear fatigue properties from uniaxial fatigue properties, which were in turn calculated from Roessle-Fatemi hardness estimation method, resulted in reasonable estimations. The performance of shear fatigue properties estimated from the Roessle-Fatemi hardness method was also used for the analysis of variable amplitude axial-torsion fatigue tests performed on three types of ductile steel. Reasonable predictions of fatigue life were observed for the analyzed variable amplitude tests, as most of the predictions fell within a factor of 3 of the experimental data. Furthermore, in order to use the Roessle-Fatemi hardness method for estimating the shear fatigue behavior of titanium alloys, this method was modified based on the uniaxial fatigue properties of titanium alloys.

Download or read book Mechanical and Fatigue Properties of Additively Manufactured Metallic Materials written by Aref Yadollahi and published by . This book was released on 2017 with total page 213 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study aims to investigate the mechanical and fatigue behavior of additively manufactured metallic materials. Several challenges associated with different metal additive manufacturing (AM) techniques (i.e. laser-powder bed fusion and direct laser deposition) have been addressed experimentally and numerically. Experiments have been carried out to study the effects of process inter-layer time interval – i.e. either building the samples one-at-a-time or multi-at-a-time (in-parallel) – on the microstructural features and mechanical properties of 316L stainless steel samples, fabricated via a direct laser deposition (DLD). Next, the effect of building orientation – i.e. the orientation in which AM parts are built – on microstructure, tensile, and fatigue behaviors of 17-4 PH stainless steel, fabricated via a laser-powder bed fusion (L-PBF) method was investigated. Afterwards, the effect of surface finishing – here, as-built versus machined – on uniaxial fatigue behavior and failure mechanisms of Inconel 718 fabricated via a laser-powder bed fusion technique was sought. The numerical studies, as part of this dissertation, aimed to model the mechanical behavior of AM materials, under monotonic and cyclic loading, based on the observations and findings from the experiments. Despite significant research efforts for optimizing process parameters, achieving a homogenous, defect-free AM product – immediately after fabrication – has not yet been fully demonstrated. Thus, one solution for ensuring the adoption of AM materials for application should center on predicting the variations in mechanical behavior of AM parts based on their resultant microstructure. In this regard, an internal state variable (ISV) plasticity-damage model was employed to quantify the damage evolution in DLD 316L SS, under tensile loading, using the microstructural features associated with the manufacturing process. Finally, fatigue behavior of AM parts has been modeled based on the crack-growth concept. Using the FASTRAN code, the fatigue-life of L-PBF Inconel 718 was accurately calculated using the size and shape of process-induced voids in the material. In addition, the maximum valley depth of the surface profile was found to be an appropriate representative of the initial surface flaw for fatigue-life prediction of AM materials in an as-built surface condition.

Download or read book Multiaxial Fatigue and Deformation written by Sreeramesh Kalluri and published by ASTM International. This book was released on 2000 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: Contains papers from a May 1999 symposium, describing state-of-the-art multiaxial testing techniques and analytical methods for characterizing fatigue and deformation behaviors of engineering materials. Papers are classified into sections on multiaxial strength of materials, multiaxial deformation,

Download or read book Mechanical Behaviour of Engineering Materials written by Joachim Roesler and published by Springer Science & Business Media. This book was released on 2007-10-16 with total page 540 pages. Available in PDF, EPUB and Kindle. Book excerpt: How do engineering materials deform when bearing mechanical loads? To answer this crucial question, the book bridges the gap between continuum mechanics and materials science. The different kinds of material deformation are explained in detail. The book also discusses the physical processes occurring during the deformation of all classes of engineering materials and shows how these materials can be strengthened to meet the design requirements. It provides the knowledge needed in selecting the appropriate engineering material for a certain design problem. This book is both a valuable textbook and a useful reference for graduate students and practising engineers.

Download or read book Advances in Multiaxial Fatigue written by David L. McDowell and published by ASTM International. This book was released on 1993 with total page 455 pages. Available in PDF, EPUB and Kindle. Book excerpt: Papers presented at the ASTM Symposium on Multiaxial Fatigue, held in San Diego, November 1991, to communicate the most recent international advances in multiaxial cyclic deformation and fatigue research as well as applications to component analysis and design. The 24 papers are grouped into five ca

Download or read book Fatigue in Friction Stir Welding written by J. Brian Jordon and published by Butterworth-Heinemann. This book was released on 2019-02-27 with total page 198 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue in Friction Stir Welding provides knowledge on how to design and fabricate high performance, fatigue resistance FSW joints. It summarizes fatigue characterizations of key FSW configurations, including butt and lap-shear joints. The book's main focus is on fatigue of aluminum alloys, but discussions of magnesium, steel, and titanium alloys are also included. The FSW process-structure-fatigue performance relationships, including tool rotation, travel speeds, and pin tools are covered, along with sections on extreme fatigue conditions and environments, including multiaxial, variable amplitude, and corrosion effects on fatigue of the FSW. From a practical design perspective, appropriate fatigue design guidelines, including engineering and microstructure-sensitive modeling approaches are discussed. Finally, an appendix with numerous representative fatigue curves for design and reference purposes completes the work. - Provides a comprehensive characterization of fatigue behavior for various FSW joints and alloy combinations, along with an in-depth presentation on crack initiation and growth mechanisms - Presents the relationships between process parameters and fatigue behavior - Discusses modeling strategies and design recommendations, along with experimental data for reference purposes