Download or read book Stable Crack Growth During the Liquid Metal Embrittlement of Aluminum by Mercury written by Dean Alan Wheeler and published by . This book was released on 1987 with total page 302 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Crack Growth Behavior of High Strength Aluminum Alloy During Liquid Metal Embrittlement by Gallium written by Brad Benson and published by . This book was released on 1990 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Mechanism of Liquid Metal Embrittlement Crack Growth in Aluminum Single Crystals and Other Metals in Liquid Metal Environments written by S. P. Lynch and published by . This book was released on 1977 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metallographic and fractographic studies of fracture in single crystals of aluminum and zinc, and in polycrystalline aluminum, cadmium and tin in liquid-metal environments and in air are described. The commonly suggested mechanism for liquid-metal embrittlement--that chemisorption of liquid-metal atoms facilitates tensile rupture of stressed interatomic bonds at crack tips--is not supported by the present observations. Rather, observations of extensive slip around crack tips and dimpled fracture surfaces suggest that crack growth in embrittling liquid-metal environments occurs by plastic flow, but with considerably less blunting occurring at crack tips than in air. It is proposed that liquid-metal embrittlement can be explained on the basis that chemisorption of liquid-metal atoms facilitates the nucleation of dislocations at crack tips. Such an effect would produce sub-critical crack growth, change the distribution of slip around cracks and reduce the extent of blunting at crack tips, but would not generally influence bulk flow characteristics. The relevance of these results to hydrogen-embrittlement, stress-corrosion cracking, and ductile versus brittle behaviour in general is discussed. (Author).

Download or read book Crack Initiation and Propagation in Metals in Liquid Mercury Using Fracture Mechanics written by J. A. Kapp and published by . This book was released on 1983 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fracture mechanics is a useful tool in the study of sub-critical crack growth. This report presents a summary of the results of several recent fracture mechanics studies of liquid metal embrittlement. Specific topics include crack growth measurements under cyclic loading conditions in 6061-T651 alloy embrittled by liquid mercury. The effect of mean stress on fatigue crack growth in a high strength-low alloy steel in mercury is discussed. Crack growth studies under static loading conditions at various temperatures in both 6061-T651 aluminum and 70/30 alpha brass embrittled by mercury are also presented. Finally, some experiments on mercury wetted 70/30 alpha brass in Mode III loading (pure shear) are presented. The results are discussed in relation to transport mechanisms. (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 The Mechanism of Liquid metal Embrittlement crack Growth in Aluminium Single Crystals and Other Metals in Liquid metal Environments written by S. P. Lynch 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 The Embrittlement of Copper 17 Atomic Aluminum Alloy by Liquid Mercury written by M. B. Ives and published by . This book was released on 1967 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: The role of plastic deformation in the initiation and propagation of cracks in Cu-17A1 alloy embrittled by liquid mercury has been studied. It is proposed that extensive plastic deformation and work hardening must occur at the crack-tip during propagation in order to raise the local flow stress to a critical level at which the maximum normal stress is equal to the cohesive strength. Strong indication is given that a 'critical applied stress' criterion for fracture is not applicable for this material. Micro-cracks are formed at weakened grain boundaries and a period of stable crack growth made over a period of increasing applied stress may be necessary before the crack is long enough to become unstable. (Author).

Download or read book Crack Growth Behavior During LME of High Strength Aluminum Alloy by Mercury written by Yi Liu and published by . This book was released on 1988 with total page 154 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Crack Growth Behavior of Aluminum Alloys Tested in Liquid Mercury written by J. A. Kapp and published by . This book was released on 1985 with total page 39 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crack growth rate measurements have been made in three mercury embrittled aluminum alloys each under three loading conditions. The alloys were 1100-0, 6061-T651, and 7075-T651. The loading conditions were fixed displacement static loading, fixed load static loading, and fatigue loading at two frequencies. The results showed that mercury cracking of aluminum was not unlike other types of embrittlement (i.e hydrogen cracking of steels). Under fixed load static conditions no crack growth was observed below a threshold stress intensity factor (KILME). At K levels greater that KILME cracks grew on the order of cm/s, while under fixed displacement loading, the crack growth rate was strongly dependent upon the strength of the alloy tested. This was attributed to crack closure. In the fatigue tests, no enhanced crack growth occurred until a critical range of stress intensity factor (Kth) was achieved. The Kth agreed well with the KILME obtained from the static tests, but the magnitude of the fatigue growth rate was substantially less than was expected based on the static loading results. Observations of the fracture surfaces in the scanning electron microscope (SEM) suggested a brittle intergranular fracture mode for the 6061-T651 and the 7075-T651 alloys under all loading conditions. The fractographic features of the 1100-0 alloy under fixed load and fatigue loading conditions were also brittle intergranular. Under fixed displacement loading the cracks grew via a ductile intergranular mode.

Download or read book Crack Growth in Mercury Embrittled Aluminum Alloys Under Cyclic and Static Loading Conditions written by Joseph A. Kapp and published by . This book was released on 1983 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: Crack growth rates were measured on three aluminum alloys under cyclic and static loading conditions in laboratory air and in liquid mercury at about +25 deg C. One alloy, 6061-T651, was tested under both loading conditions at temperatures ranging from -25 deg C to +45 deg C. Fracture mechanics techniques were used. Under cyclic loading conditions, no enhanced crack growth in mercury was measured until a critical stress intensity factor range (Delta K) was exceeded. When Delta K increased above the threshold value, the crack growth rae increased by as much as three orders of magnitude, when compared to the crack growth rate in air. From the appearance of the fracture surface the mechanism of embrittlement was deduced to be reduced cohesion. Under static loading conditions, crack velocities of centimeters per second were measured in load control. Under displacement control much slower crack velocities were measured in tow alloys. The decrease in crack velocity was attributed to crack blunting and large plastic zones. Static crack velocity and cyclic crack growth rate increased with decreasing temperature. This unusual temperature effect was related to the kinetics of adsorption of mercury on aluminum. (Author).

Download or read book Metals Abstracts written by and published by . This book was released on 1993 with total page 1218 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Embrittlement of 65 35 Brass by Solid Mercury zinc Amalgams written by William L. Stichman and published by . This book was released on 1972 with total page 168 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1987 with total page 952 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book U S Government Research Development Reports written by and published by . This book was released on 1967 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Stress Intensity Factor Dependence of Hg Al Liquid Metal Embrittlment sic written by Scott G. Keller and published by . This book was released on 2009 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: When high strength aluminum alloys are subjected to liquid metals, physical and chemical reactions ensue resulting in what is known as liquid metal embrittlement (LME). A subset of environmentally-assisted cracking, LME is exhibited when a liquid metal, e.g. Hg or Ga, comes into intimate contact with a solid metal having significant susceptibility. As mechanical loads are applied, the interaction between the two metals results in a reduction in the flow properties of the solid metal. Several theories have been proposed to identify the underlying microstructural failure mechanism; however, none have been widely accepted, as failures can typically incorporate features common to several failure theories. In an effort to confirm, extend or replace the physically-based theories, fracture mechanics experiments on Al 7075-T651 in liquid mercury have been conducted. Experiments were conducted in a custom environmental chamber capable of exposing specimens to liquid environments while applying a mechanical load. Through both plane-strain fracture and stress intensity factor-dependent (SIF) tests, fracture toughness values along with incubation periods were analyzed and provided data for a load-based theory of LME. These mechanical test data, along with metallographic analysis, show that the phenomena of LME is both strongly time- and SIF-dependent.

Download or read book Dissertation Abstracts International written by and published by . This book was released on 1993-05 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Advances in Corrosion Science and Technology written by Mars G. Fontana and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 383 pages. Available in PDF, EPUB and Kindle. Book excerpt: This series was organized to provide a forum for review papers in the area of corrosion. The aim of these reviews is to bring certain areas of corrosion science and technology into a sharp focus. The volumes of this series will be published approximately on a yearly basis and will each contain three to five reviews. The articles in each volume will be selected in such a way to be of interest both to the corrosion scientists and the corrosion tech nologists. There is, in fact, a particular aim in juxtaposing these interests because of the importance of mutual interaction and interdisciplinarity so important in corrosion studies. It is hoped that the corrosion scientists in this way may stay abreast of the activities in corrosion technology and vice versa. In this series the term "corrosion" will be used in its very broadest sense. This will include, therefore, not only the degradation of metals in aqueous environment but also what is commonly referred to as "high temperature oxidation. " Further, the plan is to be even more general than these topics; the series will include all solids and all environments. Today, engineering solids include not only metals but glasses, ionic solids, polymeric solids, and composites of these. Environments of interest must be extended to liquid metals, a wide variety of gases, nonaqueous electrolytes, and other nonaqueous liquids.