Download or read book The Rate of Fatigue crack Propagation for Two Aluminum Alloys Under Completely Reversed Loading written by Walter Illg and published by . This book was released on 1959 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Changing Stress Amplitude on the Rate of Fatigue crack Propagation in Two Aluminum Alloys written by C. M. Hudson and published by . This book was released on 1961 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: A series of fatigue tests with specimens subjected to constant amplitude and two-step axial loads were conducted on 12-inch-wide sheet specimens of 2024-T3 and 7075-T6 aluminum alloy to study the effects of a change in stress level on fatigue-crack propagation. Comparison of the results of the tests in which the specimens were tested at first a high and then a low stress level with those of the constant-stress-amplitude tests indicated that crack propagation was generally delayed after the transition to the lower stress level. In the tests in which the specimens were tested at first a low and then a high stress level, crack propagation continued at the expected rate after the change in stress levels.

Download or read book The Rate of Fatigue crack Propagation in Two Aluminum Alloys written by Arthur J. McEvily and published by . This book was released on 1958 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt: A general method has been developed for the determination of fatigue-crack propagation rates. In order to provide a check on the theoretical predictions and to evaluate certain empirical constants appearing in the expression for the rate of fatigue-crack propagation, an extensive series of tests has been conducted. Sheet specimens, 2 inches and 12 inches wide, of 2024-T3 and 7075-T6 aluminum alloys were tested in repeated tension with constant-amplitude loading. Stresses ranged up to 50 ksi, based on the initial area. Good agreement between the results and predictions was found.

Download or read book A Study of Spectrum Fatigue Crack Propagation in Two Aluminum Alloys 2 Influence of Microstructures written by Jack Telesman and published by . This book was released on 1985 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Study of Spectrum Fatigue Crack Propagation in Two Aluminum Alloys 1 Spectrum Simplification written by Jack Telesman and published by . This book was released on 1985 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effect of Stress Ratio on Fatigue crack Growth in 7075 T6 and 2024 T3 Aluminum alloy Specimens written by C. M. Hudson and published by . This book was released on 1969 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stress ratio effects on fatigue crack growth in sheet aluminum alloys.

Download or read book Fatigue Crack Propagation in 2024 T3 and 7075 T6 Aluminum Alloys at High Stresses written by Robert G. Dubensky and published by . This book was released on 1971 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fatigue Crack Growth in Aluminum Alloys written by J. D. Frandsen and published by . This book was released on 1976 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this investigation was to further the understanding of the mechanisms by which fatigue crack propagation occurs in aluminum alloys. Two basic techniques were used to investigate and simulate the events occurring within the plastic zone preceding fracture. The plastic deformation occuring within the plastic zone of the crack tip was simulated by low cycle fatigue tests. These tests were largely unsuccessful because of the significant influence the crack initiation stage has on fatigue life and a relative insensitivity to environmental effects. The response of the crack tip to tensile holds was determined by acoustically determined crack closure measurements. The limited results reported here were encouraging and the crack closure investigation offers possibilities of describing the fatigue cracks response to simple loading spectra. (Author).

Download or read book Crack Propagation Delayed Failure and Residual Static Strength of Titanium Aluminum and Stainless Steel Alloys in Aqueous Environments written by I. E. Figge and published by . This book was released on 1967 with total page 50 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Environmental Fatigue Crack Propagation of Aluminum Alloys at Low Stress Intensity Levels written by J. A. Feeney and published by . This book was released on 1969 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: The environmental fatigue crack propagation in 2024-T3, 7075-T6, and 7178-T6 was studied at low levels of cyclic amplitude of stress intensity, delta K. Both wedge force loading and remote loading techniques were employed to achieve the desired delta K levels, and preliminary experiments were designed to test their compatibility. Testing was carried out in humid air, distilled water, and 3.5% sodium chloride solution, and the observed crack growth rates compared with those in desiccated air. Later studies were also conducted in an inert reference environment with a total water content of less than 2 ppm. When the data are plotted as log delta K versus log d2a/dN, alloy 2024-T3 exhibits a marked slope transition, alloy 7075-T6 a slight slope transition, and alloy 7178-T6 a rectilinear behavior throughout the whole range of delta K studied. The basic shape of these curves is discussed in terms of state-of-stress conditions at the crack tip, frequency effects, environmental effects, strain rate sensitivity, and metallurgical structure. An attempt is also made to correlate the rate of fatigue crack propagation in a particular environment and at a particular delta K level with the fracture topography. (Author).

Download or read book Mechanisms of Fatigue Crack Propagation in Aluminum Alloys written by K. Erhardt and published by . This book was released on 1971 with total page 70 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechanisms of crack initiation and propagation in fatigue and of crack propagation under a monotonic load were studied in high strength aluminum alloys. Part I is a detailed report on the use of scanning electron microscopy in fatigue crack propagation research. The results are discussed with reference to the theories of fatigue crack propagation. Part II is a documentation of crack initiation and stage I fatigue fracture in aluminum alloys. The existence of non-propagating cracks in aluminum alloys is discussed by comparing the endurance limit and the stress intensity threshold for non-propagating fatigue cracks. Part III REPORTS THE INFLUENCE OF TEMPERATURE AND CYCLIC RATE ON CRACK GROWTH IN 2024 T3 aluminum alloy. Part IV deals with the role of the cold work of the plastic zone at the tip of a crack on the mechanisms of fatigue crack growth rate. Part V is a study of the correlation between the fracture toughnews index K and the tensile properties. This work was undertaken to understand the dependance of the critical stress intensity factor on aging, the workhardening exponent, and plane strain ductility. (Author).

Download or read book An Investigation of Fatigue Crack Growth Behavior in Cast Particulate Reinforced Aluminum Alloys written by Anthony George Keslinke and published by . This book was released on 1990 with total page 170 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Mechanisms of Fatigue Crack Growth in Particulate and Whisker Reinforced Aluminum Alloys written by James Joseph Mason and published by . This book was released on 1988 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of Fatigue crack Growth Under Simple Variable amplitude Loading written by C. M. Hudson and published by . This book was released on 1970 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: VARIABLE-AMPLITUDE FATIGUE-CRACK-GROWTH TESTS WERE CONDUCTED ON SIMPLE SHEET SPECIMENS MADE OF 7075-T6 ALUMINUM ALLOY. THE NUMBERS AND THE AMPLITUDES OF THE HIGH-LOAD CYCLES APPLIED IN THESE TESTS WERE SYSTEMATICALLY VARIED TO STUDY THEIR EFFECTS ON SUBSEQUENT LOW-LOAD FATIGUE-CRACK GROWTH. THE HIGH-LOAD CYCLES CONSISTENTLY DELAYED SUBSEQUENT FATIGUE-CRACK GROWTH AT LOWER LOAD LEVELS. FOR A GIVEN LOW-LOAD LEVEL, THE HIGHER THE PRECEDING HIGH-LOAD LEVEL WAS, THE GREATER THE DELAY IN CRACK PROPAGATION. FURTHERMORE, THE DELAY IN CRACK GROWTH INCREASED WITH INCREASING NUMBERS OF HIGH-LOAD CYCLES UP TO A LIMIT. ONE HIGH-LOAD CYCLE CAUSED APPROXIMATELY ONE-FOURTH OF THE MAXIMUM DELAY, AND TEN HIGH-LOAD CYCLES CAUSED APPROXIMATELY ONE-HALF OF THE MAXIMUM DELAY. THESE DELAYS PROBABLY RESULTED FROM RESIDUAL COMPRESSIVE STRESSES GENERATED IN THE MATERIAL IMMEDIATELY AHEAD OF THE CRACK TIP DURING THE APPLICATION OF THE HIGH-LOAD CYCLES. ELECTRON FRACTOGRAPHIC STUDIES SHOWED THAT A GIVEN STRESS LEVEL, FATIGUE CRACKS PROPAGATED MORE SLOWLY IMMEDIATELY AFTER THE APPLICATION OF A HIGH-LOAD CYCLE THAN THEY DID IMMEDIATELY BEFORE ITS APPLICATION. THIS LOWER CRACK-GROWTH RATE IS CONSISTENT WITH THE DELAY IN CRACK GROWTH OBSERVED ON THE MACROSCOPIC LEVEL.

Download or read book Effect of Stress Ratio on Fatigue Crack Growth and Mode of Fracture in 2024 T4 and 7075 T6 Aluminum Alloys in the Low cycle Range written by D. Y. Wang and published by . This book was released on 1966 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Investigation was conducted at minimum-to-maximum stress ratios R of -2.5, -2.0, -1.5, -1.0, 0.0 and 0.6. It was observed that the fracture mechanism of low-cycle fatigue involves Stage II fatigue crack growth which is characterized by the development of ductile striations and two essential types of secondary fracture surfaces. It is shown that ductile fatigue crack growth, which involves two types of ductile striations, is governed by the local irreversible plastic deformation at the crack tip in both alloys. The most important mode of secondary crack growth in 2024-T4 aluminum is the brittle fracture or decohension of the constituent particles ahead of the crack tip and the subsequent growth of the interior cracks toward the main crack. The size of the plastic zone at the crack tip appears to determine the degree of influence of this mode of fracture on overall crack growth rate. In 7075-T6, the dominant mode of secondary crack growth is the quasi-cleavage fracture of the matrix. The frequency of occurrence of these two modes of secondary crack growth increases with the stress ratio, i.e., with increasing mean stress. The change in the modes of crack growth as we change from low to high mean stress contributes to the relative differences in fatigue strength of the two materials at various stress ratios.

Download or read book Image Correlation for Shape Motion and Deformation Measurements written by Michael A. Sutton and published by Springer Science & Business Media. This book was released on 2009-04-21 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt: Image Correlation for Shape, Motion and Deformation Measurements provides a comprehensive overview of data extraction through image analysis. Readers will find and in-depth look into various single- and multi-camera models (2D-DIC and 3D-DIC), two- and three-dimensional computer vision, and volumetric digital image correlation (VDIC). Fundamentals of accurate image matching are described, along with presentations of both new methods for quantitative error estimates in correlation-based motion measurements, and the effect of out-of-plane motion on 2D measurements. Thorough appendices offer descriptions of continuum mechanics formulations, methods for local surface strain estimation and non-linear optimization, as well as terminology in statistics and probability. With equal treatment of computer vision fundamentals and techniques for practical applications, this volume is both a reference for academic and industry-based researchers and engineers, as well as a valuable companion text for appropriate vision-based educational offerings.

Download or read book Fatigue of Materials III written by Raghavan Srinivasan and published by Springer. This book was released on 2016-12-01 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume contains papers presented in the third international symposium titled Fatigue of Materials: Advances and Emergences in Understanding held during the Materials Science and Technology 2014 meeting. The book contains contributions from engineers, technologists, and scientists from academia, research laboratories, and industries. The papers are divided into six topical areas: Session 1: Aluminum Alloys Session 2: Ferrous Materials I Session 3: Ferrous Materials II Session 4: Composite Materials Session 5: Advanced Materials Session 6: Modeling The papers cover a broad spectrum of topics that represent the truly diverse nature of the subject of fatigue as it relates to the world of materials.