Download or read book Effect of Silver Addition on Mechanical Properties and Stress Corrosion Cracking in a Predeformed and Overaged 7055 Aluminum Alloy written by Mehdi Shakouri and published by . This book was released on 2018 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of silver on mechanical properties and stress corrosion cracking (SCC) resistance in a predeformed and overaged 7055 aluminum alloy was investigated. The treatment consisted of solution treating the specimens and then applying 5 % plastic deformation (compression) before aging. The next operation was aging the specimens at 121°C for 24 hours and overaging them at 175°C for 10 hours. Properties of the alloys were investigated by mechanical testing, scanning electron microscopy, transmission electron microscopy, energy-dispersive X-ray spectroscopy, X-ray diffraction, and differential scanning calorimetry. Results show that the ultimate tensile strength (UTS) and yield tensile strength (YTS) for the silver-free alloy were 580 and 520MPa, respectively, and increased to 594 and 567MPa after the addition of 0.39 % silver. Moreover, the stress corrosion resistance increased = 23 % after adding 0.2 % silver. It can be seen that the addition of silver to predeformed and overaged 7055 aluminum alloy slightly improves the UTS and YTS and increases resistance to SCC significantly. These improvements are due to the interrupting effect of silver on the continuity of magnesium-rich precipitates and the increasing copper absorption in the precipitates.

Download or read book Stress corrosion Cracking in High Strength Steels and in Titanium and Aluminum Alloys written by Benjamin Floyd Brown and published by . This book was released on 1972 with total page 388 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress corrosion Cracking of Aluminum Alloys written by J. D. Jackson and published by . This book was released on 1965 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress corrosion Cracking of Aluminum Alloys written by Gunter Ogiermann and published by . This book was released on 1968 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: The report summarizes information from selected European papers and lectures that were published or presented between mid 1967 and July 1, 1968. Subjects discussed include: the nature of stress-corrosion, stress-corrosion in AlMg, AlMgZn, and AlMgSi alloys and testing for susceptibility to stress-corrosion cracking. (Author).

Download or read book Stress corrosion Cracking of Aluminum Alloys written by F. R. Mertens and published by . This book was released on 1967 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Environmental Corrosion fatigue Behavior of Aluminum Alloys written by D. N. Williams and published by . This book was released on 1970 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effects of environment on fatigue behavior are quite intimately related to such test variables as stress intensity, cyclic frequency, and temperature. The effect of these variables has been shown to be quite complex. However, a consistent pattern of behavior is beginning to emerge which, it is hoped, will lead to a considerably changed understanding of the corrosion-fatigue process. It is considered probable that an increased understanding of the corrosion-fatigue process will also contribute measureably to an improved understanding of general fatigue processes. Material variables such as composition, directionality of properties, and microstructure, have important effects on corrosion-fatigue behavior of aluminum alloys. However, it appears that these variables, at least in gaseous environments, may be important largely because of their effects on the mechanical behavior of aluminum alloys. On the other hand, studies in seawater suggest that these variables become increasingly important as the corrosive nature of the environment increases. This memorandum discusses in detail the effects of both test variables and material variables on corrosion fatigue. In addition, current theories of corrosion-fatigue mechanisms are outlined, and several methods of preventing corrosion fatigue are suggested. (Author).

Download or read book Stress Corrosion Resistance of Silver Bearing Aluminum Alloys written by Irving S. Shaffer and published by . This book was released on 1971 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: An investigation was made to determine the effect of silver addition on the stress corrosion resistance of Al-Zn-Mg-Cu alloys. Tests were conducted by alternate immersion in 3 1/2% NaCl on two lots from two different sources. The silver bearing alloys displayed an increased susceptibility to pitting corrosion and a predominantly transgranular mode of cracking. No significant improvement in stress corrosion behavior was noted with silver addition as measured by time to cracking. (Author).

Download or read book Effect of Iron and Silicon Content on Stress Corrosion Cracking in a Thermomechanically Processed Aluminum Alloy written by P. J. Blau and published by . This book was released on 1975 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study of stress corrosion cracking in 7475 type aluminum alloy plates was conducted using five iron and silicon levels, chromium and zirconium minor additions, and two tempers: T651 and thermomechanical processing (TMP). The T651 specimens showed no clear effects of purity or minor addition on stress corrosion resistance; however, a large purity effect was seen in TMP specimens. As total iron and silicon content decreased from 0.31 to 0.02 weight percent, the 2000-hour threshold stress intensity about doubled in these alloys. In addition, TMP alloys showed a relationship between stress corrosion, threshold stress intensity, and precracked Charpy toughness. (Author).

Download or read book Corrosion of Aluminum and Aluminum Alloys written by Joseph R. Davis and published by ASM International. This book was released on 1999-01-01 with total page 338 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 Effect of Potential on the Stress Corrosion Cracking of Aluminum Alloy 7075 written by Anh Hong Le and published by . This book was released on 1982 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress corrosion Cracking of Aluminum Alloys a Review of the German Literature written by and published by . This book was released on 1967 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: The phenomenon known as stress corrosion has been defined in several ways. For example, the definition which has been accepted in England is restricted to static stress: 'The term 'stress corrosion' implies a greater deterioration in the mechanical properties of the material through the simultaneous action of the static stress and exposure to corrosive environment than would occur by the separate, but additive action of these surroundings.' This definition includes stress-accelerated corrosion, but excludes corrosion fatigue. (Author).

Download or read book Mechanisms of Stress Corrosion Cracking and Liquid Metal Embrittlement Particularly in High Strength Aluminium Alloys written by S. P. Lynch and published by . This book was released on 1977 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metallographic and fractographic observations of sub-critical crack growth in a precipitation-hardened AlZn-Mg alloy in liquid-metal, aqueous, and water-vapour/air environments suggest that stress-corrosion cracking and liquid-metal embrittlement in this alloy involve a common mechanism. Sub-critical crack growth in all these environments can produce entirely dimpled fracture surfaces and, in liquid-metal and aqueous environments, crack growth can occur extremely rapidly. It is proposed that stress-corrosion cracking and liquid-metal embrittlement in aluminium alloys (and possibly other materials) can be explained on the basis that chemisorption of environmental species facilitates nucleation of dislocations at crack tips. Such a process would produce sub-critical crack growth with less blunting at crack tips than in inert environments and, hence, would explain observations that dimples on fracture surfaces after SCC are smaller and shallower than those on overload fractures. The results suggest that neither dissolution nor hydrogen-embrittlement processes occurred during stress-corrosion cracking in aluminium alloys. (Author).

Download or read book Stress Corrosion Cracking of High Strength Aluminum Alloys written by E. N. Pugh and published by . This book was released on 1980 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt: A study has been made of the mechanism of hydrogen embrittlement (HE) in Al-Zn-Mg alloys, and of the role of hydrogen in the intergranular stress-corrosion cracking (I-SCC) of these alloys. Up to 300 ppm (1 at pct) hydrogen was introduced into a high-purity Al-5.6Zn-2.6Mg alloy, either by room temperature polishing with aqueous slurries of alumina particles or by exposure to water-vapor-saturated air (WVSA) at 70 C, and subsequent tensile tests (stress rate approx 0.0001/s) in inert environments caused brittle intergranular fracture. Embrittlement was found to be reversible, the tensile properties being completely restored when the hydrogen was outgassed. At low hydrogen contents, embrittlement was suppressed by the use of high strain rates (approx 0.01/s), but could not be suppressed by impact testing at large hydrogen concentrations. The intergranular fracture surfaces were observed to be associated with a fragmented layer, and electron-diffraction experiments indicated that it corresponded to a hexagonal aluminum hydride, Al H3, with a = 2.90 A and c = 4.55 A. This hydride, considered to be stress-induced, was unstable in laboratory air, slowly decomposing to FCC Al. It is concluded that internal HE in this alloy occurs by repeated cycles of the formation and rupture of this brittle hydride.

Download or read book Stress Corrosion Cracking of Wrought and P M High Strength Aluminum Alloys written by A. W. Thompson and published by . This book was released on 1982 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report presents results for the first year of a three-year program. The objective of this program is to understand the stress corrosion cracking (SCC) behavior of high-strength ingot and powder metallurgy aluminum alloys, and in particular to understand the role of hydrogen in such cracking. The approach taken was to study microstructural effects on both hydrogen embrittlement and SCC, and to establish, insofar as possible, microstructural and fractographic correlations with cracking behavior, and detailed understanding of the mechanical behavior of hydrogen-charged material. (Author).

Download or read book The Stress Corrosion Cracking of a Non age hardenable Aluminum Alloy written by Richard Glen Weber and published by . This book was released on 1969 with total page 74 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Seacoast Stress Corrosion Cracking of Aluminum Alloys written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-06 with total page 30 pages. Available in PDF, EPUB and Kindle. Book excerpt: The stress corrosion cracking resistance of high strength, wrought aluminum alloys in a seacoast atmosphere was investigated and the results were compared with those obtained in laboratory tests. Round tensile specimens taken from the short transverse grain direction of aluminum plate and stressed up to 100 percent of their yield strengths were exposed to the seacoast and to alternate immersion in salt water and synthetic seawater. Maximum exposure periods of one year at the seacoast, 0.3 or 0.7 of a month for alternate immersion in salt water, and three months for synthetic seawater were indicated for aluminum alloys to avoid false indications of stress corrosion cracking failure resulting from pitting. Correlation of the results was very good among the three test media using the selected exposure periods. It is concluded that either of the laboratory test media is suitable for evaluating the stress corrosion cracking performance of aluminum alloys in seacoast atmosphere. Humphries, T. S. and Nelson, E. E. Marshall Space Flight Center NASA-TM-82393