Download or read book Influence of overaging at 175 degrees C on the fatigue crack growth rate of a 7075 aluminium alloy written by Guy Ramusat and published by . This book was released on 1977 with total page 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 Effects of Bonding Temperatures on Fatigue Crack Growth written by Rodney L. Wilkinson and published by . This book was released on 1983 with total page 68 pages. Available in PDF, EPUB and Kindle. Book excerpt: Changes in the crack growth behavior of 7075-T651 aluminum specimens which has been exposed to temperatures between 150 degrees and 355 degrees F (66 deg and 179 deg C) were evaluated. Specimens were fatigue tested at room temperature under flight-by-flight loading conditions. Results from these tests were then compared with data from the baseline (as received) material. Exposure to 250 deg F (121 deg C) or more produced a definite increase in speciment life, apparently due to a decrease in crack growth rates.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1978 with total page 996 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Microstructural Effect on Fatigue of 7075 Aluminum Alloy written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This study was conducted to characterize the fatigue behavior of underaged and overaged 7075 aluminum alloy in vacuum of 4xl0(exp -8) torr. An emphasis was placed on clarifying the effects of different microstructures, arising from the underaging and overaging treatments, on the threshold fatigue crack growth (FCG). The FCG was measured under constant amplitude loading of stress ratios, ranging from 0.1 to 0.85, in vacuum of 4xl0(exp -8) torr. The result was analyzed in terms of threshold stress intensity range for FCG and maximum stress intensity. It was found that the underaging resulted in lower electrical conductivity, higher hardness, and greater resistance to threshold FCG than the overaging. This is attributable to the difference in microstructure.
Download or read book Effects of Corrosion Temperature and Overload on Fatigue Crack Growth Rate Retardation in 7075 T651 Aluminum Alloy written by Mikio Scot Oshiro and published by . This book was released on 2000 with total page 376 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Specimen Thickness on Fatigue crack growth Behavior and Fracture Toughness of 7075 T6 and 7178 T6 Aluminum Alloys written by Charles Michael Hudson and published by . This book was released on 1973 with total page 44 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Effect of Stress Ratio on Fatigue crack Growth in 7075 T6 and 2024 T3 Aluminum alloy Specimens written by C. Michael Hudson and published by . This book was released on 1969 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Environmentally Influenced Near Threshold Fatigue Crack Growth in 7075 T651 Aluminum Alloy written by and published by . This book was released on 1996 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The near-threshold fatigue crack growth behavior of a 7075-T651 aluminum alloy was studied in laboratory air, vacuum, and an aqueous 3.5% NaCl solution. Results obtained indicate that raising the stress ratio R enhanced the near-threshold fatigue crack growth with a greater crack growth rate da/dN and smaller threshold stress intensity range deltaK(th) in laboratory air and an aqueous 3.5% NaCl solution. However, the reverse was observed in vacuum. The near-threshold fatigue crack growth was most sluggish with the smallest da/dN and greatest deltaK(th) values in vacuum, intermediate with an intermediate da/dN and deltaK(th) in the aqueous 3.5% NaCl solution, and fastest with the greatest da/dN and smallest deltaK(th) values in laboratory air. In laboratory air and aqueous 3.5% NaCl solution deltaK(th) initially decreased with increasing R until a value of 0.5 was reached, and then leveled off or decreased slightly. The detlaK(th) values for these two environments appear to converge at a higher R. On the other hand, in vacuum, the deltaK(th) increased linearly with increasing R. In addition, at lower R, a greater resistance to near-threshold fatigue crack growth was detected in the aqueous 3.5% NaCl solution than in laboratory air. This is attributable to crack closure, induced by corrosion product at the crack tip.
Download or read book Environmentally Influenced Near Threshold Fatigue Crack Growth in 7075 T651 Aluminum Alloy written by HC. Sanders and published by . This book was released on 2000 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt: The near-threshold fatigue crack growth behavior of the 7075-T651 aluminum alloy was studied in laboratory air, vacuum, and an aqueous 3.5% NaCl solution. Results indicate that a rising stress ratio (R) enhanced the near-threshold fatigue crack growth by increasing the crack growth rate (da/dN) and decreasing the threshold stress intensity range (?Kth) in both laboratory air and aqueous 3.5% NaCl solution. However, the reverse was observed in vacuum. It was also noticed that the near-threshold fatigue crack growth resistance was greatest in vacuum, intermediate in aqueous 3.5% NaCl solution, and lowest in laboratory air. Conversely, the crack growth rate at given values of AK were shown to be greatest in laboratory air, less in 3.5% NaCl solution, and lowest in vacuum. In both laboratory air and aqueous 3.5% NaCl solution, ?Kth, initially decreased with increasing R until a critical stress ratio of Rc = 0.5 was reached, which it then leveled off or decreased slightly. The ?Kth values for these two environments appear to converge at a higher R. On the other hand, in vacuum, the ?Kth, increased linearly with increasing R. In addition, at lower R, a greater resistance to near-threshold fatigue crack growth was detected in aqueous 3.5% NaCl solution than in laboratory air. This is presumably attributed to crack closure that has been induced by accumulation of corrosion product in the crack-tip.
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 A Fracture Mechanics Study of Corrosion Fatigue written by R. A. M. Chandra Prasad and published by . This book was released on 2022-09-26 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Majority of industrial components fail due to the conjoint actions of fatigue and corrosion. All fatigue failures including one in air can be categorized as corrosion fatigue. Absolute fatigue can take place only in vacuum or inert environment. The effect of corrosion on fatigue has been extensively studied by determining the stress vs. number of cycles (S-N) curve. S-N curve depicts the final fracture, it does not separate the crack initiation and crack propagation. The defect tolerant design based on fracture mechanics concepts assumes that some forms of defects are already present in the materials and a considerable life in spent in crack propagation before the final fracture. Measure of resistance of a material to crack growth (fracture toughness) then becomes extremely important. It is now possible to describe material property of fracture toughness in terms of applied intensity of stress near the crack tip (K). Fracture mechanics based on elastic material behavior (absence of significant yielding) , referred to as the linear elastic fracture mechanics (LEFM) is well suited to materials which have limited ductility. The stress intensity factor (K ) is used both for conditions of static loading (Stress Corrosion Cracking) and for the moving cracks during fatigue loading . In this book the results of corrosion fatigue crack growth on 7075 - Alclad alloy are presented. This alloy is widely used in aircraft and automobile industries. Corrosion resistance is obtained by cladding with a more corrosion resistant aluminum alloy. However, the corrosion protection system may undergo rupture especially during crack growth in the underlying metal. Environment will then play a dominant role in the crack growth process. The design of reliable aircraft structures requires provision that cracks do not propagate under cyclic loading to reach a critical size resulting in fracture. The understanding of crack propagation under the conjoint action of corrosion and fatigue is thus of great technological and economic significance. Conflicting observations have been reported in literature regarding the influence of microstructure and environmental variables on the corrosion crack propagation rates.
Download or read book 7075 T6 and 2024 T351 Aluminum Alloy Fatigue Crack Growth Rate Data written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-24 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental test procedures for the development of fatigue crack growth rate data has been standardized by the American Society for Testing and Materials. Over the past 30 years several gradual changes have been made to the standard without rigorous assessment of the affect these changes have on the precision or variability of the data generated. Therefore, the ASTM committee on fatigue crack growth has initiated an international round robin test program to assess the precision and variability of test results generated using the standard E647-00. Crack growth rate data presented in this report, in support of the ASTM roundrobin, shows excellent precision and repeatability. Forth, Scott C. and Wright, Christopher W. and Johnston, William M., Jr. Langley Research Center NASA/TM-2005-213907, L-19163
Download or read book 7075 T6 and 2024 T351 Aluminum Alloy Fatigue Crack Growth Rate Data written by Nasa Technical Reports Server (Ntrs) and published by BiblioGov. This book was released on 2013-07 with total page 28 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NASA Technical Reports Server (NTRS) houses half a million publications that are a valuable means of information to researchers, teachers, students, and the general public. These documents are all aerospace related with much scientific and technical information created or funded by NASA. Some types of documents include conference papers, research reports, meeting papers, journal articles and more. This is one of those documents.
Download or read book The Effect of Overloads on Fatigue Crack Growth in 7075 T6 Aluminum written by Richard Hood and published by . This book was released on 1981 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Effect of Stress Ratio on Fatigue Crack Growth Rate at Notched Hole in 7075 T6 Aluminum Alloy Under Biaxial Fatigue written by Reja Alshahrani (Capt., RSAF.) and published by . This book was released on 2016 with total page 82 pages. Available in PDF, EPUB and Kindle. Book excerpt:
