Download or read book Evaluation of the Effect of Crack Closure on Fatigue Crack Growth of Simulated Short Cracks written by and published by . This book was released on 1984 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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:

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:

Download or read book Analysis of Fatigue Crack Closure During Simulated Threshold Testing written by RC. McClung and published by . This book was released on 2000 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: Load shedding procedures during fatigue crack growth threshold testing can, under some conditions, induce significant changes in fatigue crack closure levels, which can in turn artificially influence the apparent threshold level. In this paper, mechanics analyses of growing fatigue cracks that account for plasticity-induced closure are used to study load shed effects on crack opening levels during simulated threshold testing. Both finite element and FASTRAN strip yield models are employed, and the two approaches are compared. The current ASTM standard test method for determining thresholds is evaluated. Analyses explore the effects of initial stress, initial stress intensity factor, specimen size, material flow strength, and load shed rates on crack closure.

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:

Download or read book A Re evaluation of Fatigue Threshold Test Procedures and the Simulation and Prediction of Fatigue Crack Growth Under Conditions of Low Crack Closure written by William Alexander Herman and published by . This book was released on 1988 with total page 350 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue Testing and Analysis Under Variable Amplitude Loading Conditions written by Peter C. McKeighan and published by ASTM International. This book was released on 2005 with total page 588 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Analytical Investigation of Plasticity Induced Closure Involving Short Cracks written by E. Bednarz and published by . This book was released on 1988 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasticity induced crack closure and its effect on the fatigue growth of short cracks is investigated numerically. A plane stress finite-element analysis is used to simulate a nonpropagating crack of length 65 ?m in a single-edge-cracked specimen under two stress levels and two values of stress ratio R. A comparison of results is then made with a propagating crack of an initial length of 25 ?m, which is allowed to grow to a final length of 65 ?m. R values of 0.1 and -1.0 with stress levels of 60 and 90% of the yield stress for the material are considered. The plastic zone size for each case studied is approximately equal to the initial crack length, which provides conditions characteristic of short cracks.

Download or read book Modeling of Short Crack Growth Under Biaxial Fatigue written by H. Zenner and published by . This book was released on 2000 with total page 17 pages. Available in PDF, EPUB and Kindle. Book excerpt: Grain boundaries, microstructural barriers and differences in stress/strain state play a dominant role in the early stages of the fatigue crack growth of metals. Many studies on the growth of short cracks have revealed anomalies in the behavior predicted by LEFM analysis. A simulation of fatigue crack growth is presented. The polycrystalline metal was modeled as an aggregate of hexagonal grains with a different crystallographic orientation of each grain. The effect of grain boundaries on Stage I crack growth is considered in the model. The mode of shear crack growth is used to compute the crack growth. This mode is analyzed on the basis of microstructural crack growth within the first few grains, where the crack growth decelerates as the crack tip gets closer to the grain boundary. Normal crack growth has been considered for those cracks which are longer than microstructural cracking (physically short cracks). The transition from Stage I to Stage II growth is considered. The model is applied for thin-walled tubular specimens of the ferritic steel AISI 1015 and the aluminum alloy AlMgSi1 subjected to tension and torsion loading as well as in-phase and out-of-phase combined tension-torsion loading, sequential tension and torsion loading. The microstructural crack pattern and crack distribution can be successfully simulated with the model, and the simulated microstructural crack growth rate is presented.

Download or read book NASA Technical Memorandum written by and published by . This book was released on 1988 with total page 230 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Small Fatigue Cracks written by K.S. Ravichandran and published by Elsevier. This book was released on 1999-09-30 with total page 511 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book contains the fully peer-reviewed papers presented at the Third Engineering Foundation Conference on Small Fatigue Cracks, held under the chairmanship of K.S. Ravichandran and Y. Murakami during December 6-11, 1998, at the Turtle Bay Hilton, Oahu, Hawaii. This book presents a state-of-the-art description of the mechanics, mechanisms and applications of small fatigue cracks by most of the world's leading experts in this field. Topics ranging from the mechanisms of crack initiation, small crack behavior in metallic, intermetallic, ceramic and composite materials, experimental measurement, mechanistic and theoretical models, to the role of small cracks in fretting fatigue and the application of small crack results to the aging aircraft and high-cycle fatigue problems, are covered.

Download or read book Fatigue Crack Closure Evaluation Under Constant Amplitude and Spectrum Loading written by BK. Parida and published by . This book was released on 2003 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fatigue crack growth behavior of through-the-thickness cracks emanating from the notch root in an aluminum alloy was investigated with particular emphasis on the evaluation of crack closure and its effects on fatigue crack growth rate. The tests were performed on SE(T) specimens both under constant amplitude (CA) and spectrum (modified FALSTAFF) loads. The near-tip strain measurement method was used for crack closure estimation in the short and long crack ranges. An attempt was also made to determine the crack closure value corresponding to the crack-tip shielding through fractographic analysis.

Download or read book Crack Closure and Variable Amplitude Fatigue Crack Growth written by AJ. McEvily and published by . This book was released on 1988 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The prediction of service lifetime and the selection of alloys for maximum fatigue crack growth resistance are made complicated by the effect of prior loading histories on the rate of crack growth. Some research indicates that crack closure can be an important factor in accounting for this history effect. This paper presents a review of the lifetime on load-interaction effects on fatigue crack growth and indicates some of the future research needed to better understand the factors giving rise to history effects in the growth of long and short cracks.

Download or read book An Evaluation of the Plasticity Induced Crack Closure Concept and Measurement Methods written by James C. Newman (Jr.) and published by . This book was released on 1998 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Effects of Slip Character and Crack Closure on the Growth of Small Fatigue Cracks in Titanium aluminium Alloys written by James M. Larsen and published by . This book was released on 1990 with total page 286 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation was performed to study the effects of slip character and crack closure on the propagation of small fatigue cracks in titanium- aluminum alloys. The materials examined were solution-treated Ti-4Al and Ti-8Al, as well as aged Ti-8Al. The propagation of naturally initiated surface cracks of depths as small as 25 micrometers was compared with the behavior of large through-thickness cracks. An extensometer was used to monitor crack closure throughout the large crack tests, and the closure behavior of the small cracks was measured using a computerized laser interferometric displacement gage having a displacement resolution of 0.01 micrometer. The measurements of crack closure were used to compute an effective stress intensity factor range. In all three alloys and for all test conditions, which included a range of stress levels and stress ratios, small cracks propagated faster than large cracks subjected to an equivalent Delta K, and the small cracks propagated under conditions that were significantly below the large-crack threshold, Delta K(th). Although the character and distribution of slip in Ti-Al alloys may have a dramatic influence on fatigue crack initiation and on the propagation of large cracks, this effect was minimal for small cracks.

Download or read book Durability of Composite Systems written by Kenneth Reifsnider and published by Woodhead Publishing. This book was released on 2020-08-02 with total page 464 pages. Available in PDF, EPUB and Kindle. Book excerpt: Durability of Composite Systems meets the challenge of defining these precepts and requirements, from first principles, to applications in a diverse selection of technical fields selected to form a corpus of concepts and methodologies that define the field of durability in composite material systems as a modern discipline. That discipline includes not only the classical rigor of mechanics, physics and chemistry, but also the critical elements of thermodynamics, data analytics, and statistical uncertainty quantification as well as other requirements of the modern subject. This book provides a comprehensive summary of the field, suited to both reference and instructional use. It will be essential reading for academic and industrial researchers, materials scientists and engineers and all those working in the design, analysis and manufacture of composite material systems. Makes essential direct and detailed connections to modern concepts and methodologies, such as machine learning, systems controls, sustainable and resilient systems, and additive manufacturing Provides a careful balance between theory and practice so that presentations of details of methodology and philosophy are always driven by a context of applications and examples Condenses selected information regarding the durability of composite materials in a wide spectrum of applications in the automotive, wind energy, civil engineering, medical devices, electrical systems, aerospace and nuclear fields

Download or read book On Crack Closure in Fatigue Crack Growth written by AJ. McEvily and published by . This book was released on 1988 with total page 9 pages. Available in PDF, EPUB and Kindle. Book excerpt: A brief review of the various forms of closure is given, and the relative importance of plasticity-induced closure and roughness-induced closure is considered. On the basis of the lack of a thickness effect and an insensitivity to R in the absence of closure it is concluded that plasticity-induced closure plays a relatively minor role in affecting the rate of fatigue crack propagation with the exception of overload effects. A new form of closure, transitional closure is described and is shown to affect importantly the rate of fatigue crack growth upon a change in R ratio. The closure process for a short crack approaching a grain boundary is also discussed.