Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Fatigue Crack Closure In Residual Stress Bearing Materials
Download Fatigue Crack Closure In Residual Stress Bearing Materials full books in PDF, epub, and Kindle. Read online Fatigue Crack Closure In Residual Stress Bearing Materials ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Fatigue Crack Closure in Residual Stress Bearing Materials by : Jihwi Kim
Download or read book Fatigue Crack Closure in Residual Stress Bearing Materials written by Jihwi Kim and published by . This book was released on 2012 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: During fatigue crack growth, the two opposing faces of a fatigue crack can make physical contact while unloading from a maximum level of cyclic load, so that the crack tip state at the minimum cyclic load depends on the host geometry, material properties, and loading history. Although significant work has been performed in order to examine the effects of crack face contact, often called crack closure, under variations of applied loading history, little work has been done to understand the details of crack closure in materials that contain bulk residual stress fields. For an elastic material, variations of applied load history create changes in the crack tip behavior that are directly related to the current levels of cyclic stress, with no effect of prior loading. For an elastic-plastic material, variations of the applied load history cause the crack tip behavior to depend on the current and former loading cycles, because of plastic deformation in the crack wake. In an elastic material with bulk residual stress, crack closure occurs because the strain fields locked into the material, which are the source of the residual stress, alter the shape of the crack faces, so that the details of closure depend on the residual stress field and crack geometry. Residual stresses might therefore affect fatigue crack growth in two distinct ways: first, by combining with applied loads to affect the stress intensity factor (at the current crack size), and second, by altering crack closure. We emphasize that the effect of bulk residual stresses on crack closure described here is an elastic effect, which distinguishes it from the more commonly discussed forms of closure, such as arise from plasticity or roughness. The paper describes a means to forecast crack closure due to bulk residual stress fields and assesses schemes to account for its effects on fatigue crack growth.
Book Synopsis Mechanics of Fatigue Crack Closure by : Wolf Elber
Download or read book Mechanics of Fatigue Crack Closure written by Wolf Elber and published by ASTM International. This book was released on 1988 with total page 671 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Numerical Approach for Predicting Fatigue Crack Growth in Residual Stress Bearing Bodies by : Jihwi Kim
Download or read book Numerical Approach for Predicting Fatigue Crack Growth in Residual Stress Bearing Bodies written by Jihwi Kim and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue failure in mechanical components is one of the main concerns of the aircraft industry, so compressive residual stress is often applied to the components because it is beneficial to improve resistance to fatigue by slowing down crack growth. As a result, residual stress has been included in fatigue crack growth prediction methods. To date, residual stress was usually combined with applied loads to affect the stress intensity factor (at the current crack size) in the fatigue crack growth prediction. However, crack face contact may occur due to compressive residual stress during fatigue crack growth, and the contact effect was barely included in the prediction. Crack face contact near the crack tip under cyclic loading due to plasticity or roughness, which is called fatigue crack closure, has been studied extensively because it has a significant effect on fatigue crack growth rate (FCGR), but little research has been conducted to understand the details of crack closure due to bulk residual stress fields.This work focuses on crack closure due to compressive residual stress in an elastic material with bulk residual stress, and emphasizes that the effect of bulk residual stresses on crack closure described here is an elastic effect, which distinguishes it from the more commonly discussed forms of closure. This work describes a means to forecast crack closure due to bulk residual stress fields and assesses schemes to account for its effects on fatigue crack growth. First, contact pressure between two opposing crack faces is quantified with modeling the problem of frictionless contact. In the modeling, a weight function for a specific geometry is used and the problem is solved using quadratic mathematical programming. Second, the contact pressure is included as a form of stress intensity factor to the fatigue crack growth prediction, and the new prediction method is suggested. The new prediction method is compared to the previous methods in the literature for specific geometries (a crack on compact tension coupons and a radial crack at a hole in a strip), applied loads and residual stress fields. Additionally, in order to support this work, weight functions for cracks at a hole were newly developed.
Book Synopsis Residual Stress Effects in Fatigue by : H. S. Reemsnyder
Download or read book Residual Stress Effects in Fatigue written by H. S. Reemsnyder and published by ASTM International. This book was released on 1982 with total page 244 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Advances in Fatigue Crack Closure Measurement and Analysis by : R. Craig McClung
Download or read book Advances in Fatigue Crack Closure Measurement and Analysis written by R. Craig McClung and published by ASTM International. This book was released on 1999 with total page 487 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Fatigue Crack Growth Thresholds, Endurance Limits, and Design by : J. C. Newman
Download or read book Fatigue Crack Growth Thresholds, Endurance Limits, and Design written by J. C. Newman and published by ASTM International. This book was released on 2000 with total page 436 pages. Available in PDF, EPUB and Kindle. Book excerpt: Annotation Contains 24 papers from the November, 1998 symposium of the same name, sponsored by the ASTM Committee E8 on Fatigue and Fracture, and presented by Newman and Piascik (both of the NASA Langley Research Center). The papers focus on such areas as fatigue-crack growth threshold mechanisms, loading and specimen-type effects, analyses of fatigue-crack-growth-threshold behavior, and applications of threshold concepts and endurance limits to aerospace and structural materials. Annotation copyrighted by Book News, Inc., Portland, OR.
Book Synopsis The Effect of Residual Stress and Crack Closure on Fatigue Crack Growth by : Jonathan R. T. Lloyd
Download or read book The Effect of Residual Stress and Crack Closure on Fatigue Crack Growth written by Jonathan R. T. Lloyd and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Fatigue Crack Growth under Spectrum Loads by :
Download or read book Fatigue Crack Growth under Spectrum Loads written by and published by ASTM International. This book was released on 1976 with total page 362 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Handbook of Fatigue Crack Propagation in Metallic Structures by : A. Carpinteri
Download or read book Handbook of Fatigue Crack Propagation in Metallic Structures written by A. Carpinteri and published by Newnes. This book was released on 2012-12-02 with total page 834 pages. Available in PDF, EPUB and Kindle. Book excerpt: The purpose of this Handbook is to provide a review of the knowledge and experiences in the field of fatigue fracture mechanics. It is well-known that engineering structures can fail due to cyclic loading. For instance, a cyclically time-varying loading reduces the structure strength and can provoke a fatigue failure consisting of three stages: (a) crack initiation (b) crack propagation and (c) catastrophic failure. Since last century many scientists have tried to understand the reasons for the above-mentioned failures and how to prevent them. This Handbook contains valuable contributions from leading experts within the international scientific community and covers many of the important problems associated with the fatigue phenomena in civil, mechanical and nuclear engineering.
Book Synopsis Fatigue Crack Growth Under Variable Amplitude Loading by : J. Petit
Download or read book Fatigue Crack Growth Under Variable Amplitude Loading written by J. Petit and published by Springer. This book was released on 1988-12-31 with total page 422 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Fatigue Damage, Crack Growth and Life Prediction by : F. Ellyin
Download or read book Fatigue Damage, Crack Growth and Life Prediction written by F. Ellyin and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 484 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue failure is a multi-stage process. It begins with the initiation of cracks, and with continued cyclic loading the cracks propagate, finally leading to the rupture of a component or specimen. The demarcation between the above stages is not well-defined. Depending upon the scale of interest, the variation may span three orders of magnitude. For example, to a material scientist an initiated crack may be of the order of a micron, whereas for an engineer it can be of the order of a millimetre. It is not surprising therefore to see that investigation of the fatigue process has followed different paths depending upon the scale of phenomenon under investigation. Interest in the study of fatigue failure increased with the advent of industrial ization. Because of the urgent need to design against fatigue failure, early investiga tors focused on prototype testing and proposed failure criteria similar to design formulae. Thus, a methodology developed whereby the fatigue theories were proposed based on experimental observations, albeit at times with limited scope. This type of phenomenological approach progressed rapidly during the past four decades as closed-loop testing machines became available.
Book Synopsis The Effects of Processing Residual Stresses on the Fatigue Crack Growth Behavior of Structural Materials by : Christopher James Lammi
Download or read book The Effects of Processing Residual Stresses on the Fatigue Crack Growth Behavior of Structural Materials written by Christopher James Lammi and published by . This book was released on 2009 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Residual stresses are a common and often undesired result of material processing, introduced through non-linear deformation and/or phase transformation of material under mechanical or thermo-mechanical loading. These macro stresses alter mechanical properties and the intrinsic fatigue crack growth characteristics of the material. Residual stress artifacts can introduce inconsistencies and significant errors when the true material behavior is needed for material development and optimization and for structural component design. The effects of quenching residual stresses on fatigue crack propagation behavior of various materials were investigated. In parallel, residual stresses similar in magnitude and distribution with the quenching residual stresses were generated using mechanical processes to decouple the effects of residual stresses from microstructural effects. Mechanical residual stress distributions predicted by 3D elastic-plastic finite element analysis showed good agreement with the stresses measured on fatigue crack growth testing specimens using fracture mechanics approaches. Crack propagation characteristics in fields with low and high residual stresses were studied using optical and scanning electron microscopy, and the effects of residual stress on crack path behavior were assessed. An original residual stress analytical correction to fatigue crack growth data was developed, compared to existing corrective methodologies, and validated using residual stress free data. Overall, the work provides tools to understand, control, and correct the effects of processing residual stresses on fatigue crack growth for accurate fatigue critical design and life predictions.
Book Synopsis Predictions of Fatigue Crack Growth Behavior Using a Crack Closure Ligament Model by : F. Keyvanfar
Download or read book Predictions of Fatigue Crack Growth Behavior Using a Crack Closure Ligament Model written by F. Keyvanfar and published by . This book was released on 1988 with total page 23 pages. Available in PDF, EPUB and Kindle. Book excerpt: A ligament model, which performs a simplified, one-dimensional elastic-plastic analysis to predict fatigue crack closure behavior, is described. The model is a modification and extension of a similar one developed by Newman and has the ability to predict the influence of pre-existing residual stress fields on crack closure. Different aspects of the model are examined and, where possible, compared with experimental data and with results from theoretical studies in the literature. For specimens without pre-existing residual stresses, the aspects examined include prediction of plasticity and closure induced residual stresses near the crack tip and prediction of the influence of applied mean stress on crack opening stress. For specimens with pre-existing residual stresses, aspects examined include prediction of residual stress redistribution caused by crack growth and prediction of the influence of such stresses on crack growth behavior, using the closure concept of an effective stress intensity range. Predictions of crack growth are also compared to those based on the superposition approach, for both compressive and tensile residual stresses.
Book Synopsis Analysis of Fatigue Crack Growth and Residual Stress by : Shakhrukh Ismonov
Download or read book Analysis of Fatigue Crack Growth and Residual Stress written by Shakhrukh Ismonov and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The first part of this dissertation employs a three-dimensional elastic-plastic finite element model of straight-through crack growth to correlate four well-known methodologies characterizing fatigue crack closure. The compliance offset and the adjusted compliance ratio (ACR) are experimental methods, whereas the node displacement and the contact stress methods are numerical approaches. Evolutions of crack closure from all four methodologies are compared for a numerical model of a single edge-cracked tension specimen subjected to different levels of constant amplitude cyclic loading. In the second part, a detailed two dimensional stress analysis is conducted for a single pin-joint under plane stress conditions. This study investigates the influence of material nonlinearity, friction, and pre-existing residual stresses from cold-working process on the local radial and hoop stress levels around the pin-loaded hole. Next, the beneficial influence of cold working process is quantified by computing the Mode I stress intensity factors K[subscript I] for a single radial crack emanating from a side of a loaded hole. Two different loading configurations are considered: (a) an open hole in tension, (b) a pin-loaded hole. The stress intensity factors are computed using the J integral solutions and the weight functions specific to the crack configuration. The reductions in K[subscript I] values due to different levels of cold-working process are presented for a range of crack lengths. The final part of the research involves a numerical investigation of an on-line crack compliance technique that is used for experimental measurements of residual stress fields along the crack growth path. A finite rectangular sheet is considered with a single crack emanating from a side of a central hole. The residual stress field is introduced around the hole by cold-working simulation. As part of validation, the normalized residual stress intensity factors computed using the on-line crack compliance technique are compared with those from the J-integral approach for the case of elastic crack growth. The influence of crack tip plasticity on the performance of the on-line crack compliance technique is studied by comparing the solutions of the elastic and elastic-plastic crack growth models.
Book Synopsis Fatigue Crack Growth by : R. A. Smith
Download or read book Fatigue Crack Growth written by R. A. Smith and published by Pergamon. This book was released on 1986 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Experimental Determination of Crack Closure by the Cut Compliance Technique by : H-J Schindler
Download or read book Experimental Determination of Crack Closure by the Cut Compliance Technique written by H-J Schindler and published by . This book was released on 1999 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: The cut compliance method was developed to measure residual stress profiles. Its idea is to release them by introducing progressively a cut into the considered body. From the strain change due to progressive cutting it is possible to calculate the distribution of the released stresses. Since the method uses fracture mechanics principles the stress intensity factor due to residual stresses is delivered as well. Being a special type of residual stresses, the distribution of the contact stresses of fatigue crack closure and the corresponding closure stress intensity factors can be suitably determined by this method. Furthermore, it enables the residual stresses in front of the crack tip to be determined, which in crack retardation play a role as important as the closure effects. The basic theoretical relations for some frequently used fatigue specimens are analytically derived. They also can serve to evaluate the contact stresses from the commonly used unloading compliance technique, which is often used to identify crack closure effects. Some preliminary examples demonstrate the capability of the suggested method.
Book Synopsis Fatigue Crack Closure Outside a Small-Scale Yielding Regime by : PL. Lalor
Download or read book Fatigue Crack Closure Outside a Small-Scale Yielding Regime written by PL. Lalor and published by . This book was released on 1988 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: An elasto-plastic finite-element model has been developed to simulate fatigue crack growth and to establish crack opening levels in a notched member. Intermediate and high stress levels where small-scale yielding conditions no longer prevail were considered. Variations in crack opening and closure levels with crack length, stress state, R ratio, stress level, and degree of strain hardening were examined. Cracks were allowed to generate their own plastic wake upon advance from the notch surface. Restricting the development of a full plastic wake resulted in lower asymptotic closure levels for certain cases. Complete (R = -1) and partial (R = 0) closure of crack surfaces and the ensuing residual stresses in the crack wake were determined and linked to the crack length effect on closure. Two states of stress (plane strain and plane stress) were considered. Differences in closure levels between the two stress states developed as the crack grew from the notch.
