Fatigue Failure Of Metals

The studies on the phenomena of fatigue in metals, and especially on the formation and growth rate of cracks have been conducted in 1972-1974 with continued intensity. Their results contribute to expanding our knowledge and give us a new insight into the sphere of metal fatigue which is a highly interdiscipline field. This makes the continuous amending and modifying of books on metal fatigue a necessity, unfortunately often related with the not easy task of changing one's opinions and critical analysis of established earlier notions. These aims were my chief concern when preparing the present edition of my book in which I made use of carefully selected new information from 1972-1973 and partly 1974 reports. This new matter has been included in many instances just to signal new facts or findings, since the limited space did not allow me to give them the amount of consideration they deserve. The book has been further supplemented with the results of micrographic studies conducted in co-operation with J. Kozubowski for which lowe him special thanks. I am also indebted to Mr. H. Mughrabi from Stuttgart for allowing me to publish in this book his very interesting micrographs of dislocation structures. Finally I should like to express my sincere thanks to Mr. E. Lepa for his concern in producing a good English translation of my book.

Fatigue of Metals provides a general account of the failure of metals due to fatigue, a subject of great practical importance in the field of engineering and metallurgy. The book covers a wide range of topics on the study of the fatigue of metals. The text presents in the first three chapters the characteristics and detection of fatigue fractures; methods of fatigue testing; and the fatigue strengths of different materials. The resistance of materials to fatigue under complex stress; the determination and effects of stress concentration; influence of surface treatment on fatigue strength; and effects of corrosion and temperature are also studied in detail. In relation to the previous chapters of fatigue information, a chapter is devoted to engineering design to prevent fatigue. The last two chapters provide a brief historical survey of the developments of the study of the mechanism of fatigue and fatigue of non-metallic materials such as wood, plastic, rubber, glass, and concrete. Mechanical engineers, designers, metallurgists, researchers, and students will find the book as a good reference material.

The studies on the phenomena of fatigue in metals, and especially on the formation and growth rate of cracks have been conducted in 1972-1974 with continued intensity. Their results contribute to expanding our knowledge and give us a new insight into the sphere of metal fatigue which is a highly interdiscipline field. This makes the continuous amending and modifying of books on metal fatigue a necessity, unfortunately often related with the not easy task of changing one's opinions and critical analysis of established earlier notions. These aims were my chief concern when preparing the present edition of my book in which I made use of carefully selected new information from 1972-1973 and partly 1974 reports. This new matter has been included in many instances just to signal new facts or findings, since the limited space did not allow me to give them the amount of consideration they deserve. The book has been further supplemented with the results of micrographic studies conducted in co-operation with J. Kozubowski for which lowe him special thanks. I am also indebted to Mr. H. Mughrabi from Stuttgart for allowing me to publish in this book his very interesting micrographs of dislocation structures. Finally I should like to express my sincere thanks to Mr. E. Lepa for his concern in producing a good English translation of my book.

This book presents experimental results and theoretical advances in the field of ultra-low-cycle fatigue failure of metal structures under strong earthquakes, where the dominant failure mechanism is ductile fracture. Studies on ultra-low-cycle fatigue failure of metal materials and structures have caught the interest of engineers and researchers from various disciplines, such as material, civil and mechanical engineering. Pursuing a holistic approach, the book establishes a fundamental framework for this topic, while also highlighting the importance of theoretical analysis and experimental results in the fracture evaluation of metal structures under seismic loading. Accordingly, it offers a valuable resource for undergraduate and graduate students interested in ultra-low-cycle fatigue, researchers investigating steel and aluminum structures, and structural engineers working on applications related to cyclic large plastic loading conditions.

This textbook, suitable for students, researchers and engineers, gathers the experience of more than 20 years of teaching fracture mechanics, fatigue and corrosion to professional engineers and running experimental tests and verifications to solve practical problems in engineering applications. As such, it is a comprehensive blend of fundamental knowledge and technical tools to address the issues of fatigue and corrosion. The book initiates with a systematic description of fatigue from a phenomenological point of view, since the early signs of submicroscopic damage in few surface grains and continues describing, step by step, how these precursors develop to become mechanically small cracks and, eventually, macrocracks whose growth is governed by fracture mechanics. But fracture mechanics is also introduced to analyze stress corrosion and corrosion assisted fatigue in a rather advanced fashion. The author dedicates a particular attention to corrosion starting with an electrochemical treatment that mechanical engineers with a rather limited knowledge of electrochemistry will well digest without any pain. The electrochemical introduction is considered an essential requirement to the full understanding of corrosion that is essentially an electrochemical process. All stress corrosion aspects are treated, from the generalized film rupture-anodic dissolution process that is the base of any corrosion mechanism to the aggression occurring in either mechanically or thermally sensitized alloys up to the universe of hydrogen embrittlement, which is described in all its possible modes of appearance. Multiaxial fatigue and out-of-phase loading conditions are treated in a rather comprehensive manner together with damage progression and accumulation that are not linear processes. Load spectra are analyzed also in the frequency domain using the Fourier transform in a rather elegant fashion full of applications that are generally not considered at all in fatigue textbooks, yet they deserve a special place and attention. The issue of fatigue cannot be treated without a probabilistic approach unless the designer accepts the shame of one-out-of-two pieces failure. The reader is fully introduced to the most promising and advanced analytical tools that do not require a normal or lognormal distribution of the experimental data, which is the most common case in fatigue. But the probabilistic approach is also used to introduce the fundamental issue of process volume that is the base of any engineering application of fatigue, from the probability of failure to the notch effect, from the metallurgical variability and size effect to the load type effect. Fractography plays a fundamental role in the post mortem analysis of fatigue and corrosion failures since it can unveil the mystery encrypted in any failure.