Environmental Effects on the Fatigue Performance of 7050 Aluminum PDF Download
Are you looking for read ebook online? Search for your book and save it on your Kindle device, PC, phones or tablets. Download Environmental Effects on the Fatigue Performance of 7050 Aluminum PDF full book. Access full book title Environmental Effects on the Fatigue Performance of 7050 Aluminum by George S. Owens. Download full books in PDF and EPUB format.
Author: George S. Owens
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: George S. Owens
Publisher:
ISBN:
Category :
Languages : en
Pages :
Get Book Here
Book Description
Author: D. N. Williams
Publisher:
ISBN:
Category : Aluminum alloys
Languages : en
Pages : 22
Get Book Here
Book Description
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).
Author: Harold Luong
Publisher:
ISBN:
Category :
Languages : en
Pages : 196
Get Book Here
Book Description
Author: Phalgun Nelaturu
Publisher:
ISBN:
Category : Aluminum alloys
Languages : en
Pages : 87
Get Book Here
Book Description
Metal fatigue is a recurring problem for metallurgists and materials engineers, especially in structural applications. It has been responsible for many disastrous accidents and tragedies in history. Understanding the micro-mechanisms during cyclic deformation and combating fatigue failure has remained a grand challenge. Environmental effects, like temperature or a corrosive medium, further worsen and complicate the problem. Ultimate design against fatigue must come from a materials perspective with a fundamental understanding of the interaction of microstructural features with dislocations, under the influence of stress, temperature, and other factors. This research endeavors to contribute to the current understanding of the fatigue failure mechanisms. Cast aluminum alloys are susceptible to fatigue failure due to the presence of defects in the microstructure like casting porosities, non-metallic inclusions, non-uniform distribution of secondary phases, etc. Friction stir processing (FSP), an emerging solid state processing technique, is an effective tool to refine and homogenize the cast microstructure of an alloy. In this work, the effect of FSP on the microstructure of an A356 cast aluminum alloy, and the resulting effect on its tensile and fatigue behavior have been studied. The main focus is on crack initiation and propagation mechanisms, and how stage I and stage II cracks interact with the different microstructural features. Three unique microstructural conditions have been tested for fatigue performance at room temperature, 150 °C and 200 °C. Detailed fractography has been performed using optical microscopy, scanning electron microscopy (SEM) and electron back scattered diffraction (EBSD). These tools have also been utilized to characterize microstructural aspects like grain size, eutectic silicon particle size and distribution. Cyclic deformation at low temperatures is very sensitive to the microstructural distribution in this alloy. The findings from the room temperature fatigue tests highlight the important role played by persistent slip bands (PSBs) in fatigue crack initiation. At room temperature, cracks initiate along PSBs in the absence of other defects/stress risers, and grow transgranularly. Their propagation is retarded when they encounter grain boundaries. Another major finding is the complete transition of the mode of fatigue cracking from transgranular to intergranular, at 200 °C. This occurs when PSBs form in adjacent grains and impinge on grain boundaries, raising the stress concentration at these locations. This initiates cracks along the grain boundaries. At these temperatures, cyclic deformation is no longer microstructure- dependent. Grain boundaries don't impede the progress of cracks, instead aid in their propagation. This work has extended the current understanding of fatigue cracking mechanisms in A356 Al alloys to elevated temperatures.
Author: Theresa Elizabeth Pistochini
Publisher:
ISBN:
Category :
Languages : en
Pages : 222
Get Book Here
Book Description
Author: L. B. Vogelesang
Publisher:
ISBN:
Category :
Languages : en
Pages : 25
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category :
Languages : en
Pages : 33
Get Book Here
Book Description
Advances in our knowledge of the influence of environment on fatigue properties in recent years are reviewed. Much of this has occurred as a result of increased activity in development of water and gas nuclear reactors, heat transfer systems, and offshore structures. Effects of both aqueous and gaseous environments on crack initiation and propagation as well as fatigue life in principally steels, aluminum alloys, and titanium alloys are discussed including the role of environmental factors such as electrochemical potential, solution chemistry, gaseous species, and temperature. Mechanical factors such as frequency and loading waveform are also important in the response of material behavior to environment. (Author).
Author: Krishnan K. Sankaran
Publisher: Elsevier
ISBN: 0128120258
Category : Technology & Engineering
Languages : en
Pages : 508
Get Book Here
Book Description
Metallurgy and Design of Alloys with Hierarchical Microstructures covers the fundamentals of processing-microstructure-property relationships and how multiple properties are balanced and optimized in materials with hierarchical microstructures widely used in critical applications. The discussion is based principally on metallic materials used in aircraft structures; however, because they have sufficiently diverse microstructures, the underlying principles can easily be extended to other materials systems. With the increasing microstructural complexity of structural materials, it is important for students, academic researchers and practicing engineers to possess the knowledge of how materials are optimized and how they will behave in service. The book integrates aspects of computational materials science, physical metallurgy, alloy design, process design, and structure-properties relationships, in a manner not done before. It fills a knowledge gap in the interrelationships of multiple microstructural and deformation mechanisms by applying the concepts and tools of designing microstructures for achieving combinations of engineering properties—such as strength, corrosion resistance, durability and damage tolerance in multi-component materials—used for critical structural applications. Discusses the science behind the properties and performance of advanced metallic materials Provides for the efficient design of materials and processes to satisfy targeted performance in materials and structures Enables the selection and development of new alloys for specific applications based upon evaluation of their microstructure as illustrated in this work
Author: Chang-Soon Lee
Publisher:
ISBN:
Category :
Languages : en
Pages : 188
Get Book Here
Book Description
Author:
Publisher:
ISBN:
Category : Aeronautics
Languages : en
Pages : 1102
Get Book Here
Book Description
