Download or read book Atomistics of Fracture written by R.M. Latanison and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 1043 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is now more than 100 years since certain detrimental effects on the ductility of iron were first associated with the presence of hydrogen. Not only is hydrogen embrittlement still a major industri al problem, but it is safe to say that in a mechanistic sense we still do not know what hydrogen (but not nitrogen or oxygen, for example) does on an atomic scale to induce this degradation. The same applies to other examples of environmentally-induced fracture: what is it about the ubiquitous chloride ion that induces premature catastrophic fracture (stress corrosion cracking) of ordinarily ductile austenitic stainless steels? Why, moreover, are halide ions troublesome but the nitrate or sulfate anions not deleterious to such stainless steels? Likewise, why are some solid metals embrit tled catastrophically by same liquid metals (liquid metal embrit tlement) - copper and aluminum, for example, are embrittled by liquid mercury. In short, despite all that we may know about the materials science and mechanics of fracture on a macroscopic scale, we know little about the atomistics of fracture in the absence of environmental interactions and even less when embrittlement phe nomena such as those described above are involved. On the other hand, it is interesting to note that physical chemists and surface chemists also have interests in the same kinds of interactions that occur on an atomic scale when metals such as nickel or platinum are used, for example, as catalysts for chemical reactions.
Download or read book Atomistic Modeling of Materials Failure written by Markus J. Buehler and published by Springer Science & Business Media. This book was released on 2008-08-07 with total page 547 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an introduction to molecular and atomistic modeling techniques applied to fracture and deformation of solids, focusing on a variety of brittle, ductile, geometrically confined and biological materials. The overview includes computational methods and techniques operating at the atomic scale, and describes how these techniques can be used to model cracks and other deformation mechanisms. The book aims to make new molecular modeling techniques available to a wider community.
Download or read book General Overview Atomistics of Environmentally Induced Fracture written by R. M. Latanision and published by . This book was released on 1981 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The objective of this paper is to provide a general overview of some of the phenomenology related to the atomistics of (particularly, environmentally-induced) fracture and of those areas where interdisciplinary activity involving materials science, mechanics, physical chemistry, surface physics and chemistry and atomic modeling might provide valuable insight.
Download or read book Fracture of Brittle Solids written by Brian Lawn and published by Cambridge University Press. This book was released on 2010-01-14 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an advanced text for higher degree materials science students and researchers concerned with the strength of highly brittle covalent-ionic solids, principally ceramics. It is a reconstructed and greatly expanded edition of a book first published in 1975. The book presents a unified continuum, microstructural and atomistic treatment of modern day fracture mechanics from a materials perspective. Particular attention is directed to the basic elements of bonding and microstructure that govern the intrinsic toughness of ceramics. These elements hold the key to the future of ceramics as high-technology materials--to make brittle solids strong, we must first understand what makes them weak. The underlying theme of the book is the fundamental Griffith energy-balance concept of crack propagation. The early chapters develop fracture mechanics from the traditional continuum perspective, with attention to linear and nonlinear crack-tip fields, equilibrium and non-equilibrium crack states. It then describes the atomic structure of sharp cracks, the topical subject of crack-microstructure interactions in ceramics, with special focus on the concepts of crack-tip shielding and crack-resistance curves, and finally deals with indentation fracture, flaws and structural reliability.
Download or read book Mechanical Properties of Metals written by C. W. Lung and published by World Scientific. This book was released on 1999 with total page 442 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book is intended to describe the basic and newly developed elements of the physics of solids and materials science on mechanical properties of metals with as much continuity as is possible. Particular emphasis has been placed in atomistic and fractal approaches and continuum theory of dislocations is also introduced. Since the book is meant for the two main topics of progress in recent years, some interesting and important topics which have not been discussed or introduced are given in detail.For a long time, pair potentials were used very expensively in simulation studies. They can reproduce usefully total energies for many systems. But when one turns to elastic properties, fracture of surfaces, and the vacancy formation energy, deficiencies and limitations begin to emerge. These limitations of the simple pair potential approximation have been addressed by the development of empirical many-body potentials which is the major theme of our book.Over a decade or more, diverse scientists have recognized that many of the structures common in their experiments have a special kind of geometrical complexity. The key to this progress is the recognition that many random structures obey a symmetry that objects look the same on many different scales of observation. The concept of fractals was introduced by Mandelbrot and applied to fractures by himself and collaborators. Their work pointed to a correlation between toughness and the fractal dimension. Our interest is the fractal aspects of fractured surfaces. We will discuss more in our book.The strain field of a dislocation has a long range part and this part can be discussed rigorously from elasticity theory. Recent progress in elastic strain fields and dislocation mobility were made by Indenbom and Lothe. The elementary essentials will be introduced in our book.
Download or read book Fracture Nanomechanics written by Takayuki Kitamura and published by CRC Press. This book was released on 2011-09-06 with total page 306 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small structures of the micro/nanometer scale, such as electronic/optic devices and MEMS/NEMS have been developed, and the size of their elements now approaches the nano/atomic scale. This book discuses the fracture behavior of nano/atomic elements (nanofilms, nanowires, and so on) and focuses on the initiation and propagation of interface crack and mechanical instability criterion of atomic structures. This covers the fundamentals and the applicability of the top-down (conventional fracture mechanics to nanoscale) and bottom-up (atomic mechanics including ab initio simulation) concepts. New areas, such as multiphysics characteristics of nanoelements, are introduced as well.
Download or read book Configurational Forces written by Gerard A. Maugin and published by CRC Press. This book was released on 2016-04-19 with total page 562 pages. Available in PDF, EPUB and Kindle. Book excerpt: Exploring recent developments in continuum mechanics, Configurational Forces: Thermomechanics, Physics, Mathematics, and Numerics presents the general framework for configurational forces. It also covers a range of applications in engineering and condensed matter physics. The author presents the fundamentals of accepted standard continuum mechanics, before introducing Eshelby material stress, field theory, variational formulations, Noether’s theorem, and the resulting conservation laws. In the chapter on complex continua, he compares the classical perspective of B.D. Coleman and W. Noll with the viewpoint linked to abstract field theory. He then describes the important notion of local structural rearrangement and its relationship to Eshelby stress. After looking at the relevance of Eshelby stress in the thermodynamic description of singular interfaces, the text focuses on fracture problems, microstructured media, systems with mass exchanges, and electromagnetic deformable media. The concluding chapters discuss the exploitation of the canonical conservation law of momentum in nonlinear wave propagation, the application of canonical-momentum conservation law and material force in numerical schemes, and similarities of fluid mechanics and aerodynamics. Written by a long-time researcher in mechanical engineering, this book provides a detailed treatment of the theory of configurational forces—one of the latest and most fruitful advances in macroscopic field theories. Through many applications, it shows the depth and efficiency of this theory.
Download or read book The Physics of Deformation and Fracture of Polymers written by A. S. Argon and published by Cambridge University Press. This book was released on 2013-03-07 with total page 535 pages. Available in PDF, EPUB and Kindle. Book excerpt: A physical, mechanism-based presentation of the plasticity and fracture of polymers, covering industrial scale applications through to nanoscale biofluidic devices.
Download or read book Fracture Mechanics written by Surjya Kumar Maiti and published by Cambridge University Press. This book was released on 2015-10 with total page 301 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book offers detailed treatment on fundamental concepts of fracture mechanics. The text is useful for undergraduate students, graduate students and researchers.
Download or read book Improving Atomistic Simulations to Predict Deformation and Fracture written by Kristopher Learion Baker and published by . This book was released on 2012 with total page 150 pages. Available in PDF, EPUB and Kindle. Book excerpt: Atomistic simulations can illuminate detailed mechanisms of brittle and ductile fracture and plasticity. However, there are many limitations to these simulations like short timescales, small spatial scales, and limitations of the discretization. Using molecular dynamics (MD) and multiscale methods, adaptations can be made to allow MD to answer problems relevant to engineers. In the first of three examples, MD is adapted to simulate brittle fracture by changing the discretization and allowing permanent damage between particles. By changing the discretization, specific mechanisms inherent to MD can be suppressed to allow accurate, macroscopic simulations of dynamic fragmentation of brittle materials. Second, the timescale available to MD is extended in a concurrent multiscale method (CADD) combined with accelerated MD. This combined approach allows for microseconds of simulation time at experimentally achievable loading rates. The method is applied to crack opening in aluminum alloys, and the effect of the loading rate on crack growth mechanisms is observed. From the results, it is clear that crack growth mechanisms depend greatly on the rate of the far-field loading. Third, the effect of aging on fatigue crack growth is studied by varying the resistance to dislocation motion in the dislocation dynamics region of CADD. Only in a multiscale simulation like CADD, can dislocation pileups reaching microns into the material interact with the atomic-scale mechanisms at a crack tip. The results of the simulations indicated that increasing the friction force raises the fatigue crack threshold. Also, a transition from stage I fatigue crack growth to stage II fatigue crack growth occurs by dislocations shielding dislocation nucleation on the primary slip plane. These observations support the conclusion that the fatigue crack growth threshold is controlled by the spacing between obstacles to dislocation glide, which is consistent with experimental observations.
Download or read book Fundamentals of Hydrogen Embrittlement written by Michihiko Nagumo and published by Springer Nature. This book was released on 2023-05-22 with total page 316 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is the second edition of the one originally published in 2016, as the first comprehensive treatment on the fundamentals of hydrogen embrittlement of metallic materials, mainly steel. The book provides students and researchers engaging in hydrogen problems with a unified view of the subject. Establishing reliable principles for materials design against hydrogen embrittlement and assessing their performance are recent urgent industrial needs in developing high-strength steel for hydrogen energy equipment and weight-reducing vehicles. The interdisciplinary nature of the subject, covering metal physics, materials science, and mechanics of fracture, has disturbed a profound understanding of the problem. In this book, previous studies are critically reviewed, and supplemental descriptions of fundamental ideas are presented when necessary. Emphasis is placed on experimental facts, with particular attention to their implication rather than phenomenological appearance. The adopted experimental conditions are also noted since the operating mechanism of hydrogen might differ by material and environment. For theories, employed assumptions and premises are noted to examine their versatility. Progress in the past decade in experimental and theoretical tools is remarkable and has nearly unveiled characteristic features of hydrogen embrittlement. Proposed models have almost covered feasible aspects of the function of hydrogen. This second edition has enriched the contents with recent crucial findings. Chapters on the manifestation of embrittlement in the deterioration of mechanical properties and microscopic features are reorganized, and the description is revised for the convenience of readers’ systematic understanding. A new chapter is created for delayed fracture in atmospheric environments as a conclusive subject of critical ideas presented in this book.
Download or read book Chemistry and Physics of Fracture written by R.M. Latanision and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 726 pages. Available in PDF, EPUB and Kindle. Book excerpt: For many years it has been recognized that engineering materials that are-tough and ductile can be rendered susceptible to premature fracture through their reaction with the environment. Over 100 years ago, Reynolds associated hydrogen with detrimental effects on the ductility of iron. The "season cracking" of brass has been a known problem for dec ades, but the mechanisms for this stress-corrosion process are only today being elucidated. In more recent times, the mechanical properties of most engineering materials have been shown to be adversely affected by hydrogen embrittlement or stress-corrosion cracking. Early studies of environmental effects on crack growth attempted to identify a unified theory to explain the crack growth behavior of groups of materials in a variety of environments. It is currently understood that there are numerous stress-corrosion processes some of which may be common to several materials, but that the crack growth behavior of a given material is dependent on microstructure, microchemistry, mechanics, surface chemistry, and solution chemistry. Although the mechanism by which various chemical species in the environment may cause cracks to propagate in some materials but not in others is very complex, the net result of all environmentally induced fracture is the reduction in the force and energy associated with the tensile or shear separation of atoms at the crack tip.
Download or read book Concrete Fracture written by Jan G.M. van Mier and published by CRC Press. This book was released on 2012-10-25 with total page 383 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of fracture mechanics of concrete has developed in recent years to the point where it can be used for assessing the durability of concrete structures and for the development of new concrete materials. The last decade has seen a gradual shift of interest toward fracture studies at increasingly smaller sizes and scales. Concrete Fracture: A Multiscale Approach explores fracture properties of cement and concrete based on their actual material structure. Concrete is a complex hierarchical material, containing material structural elements spanning scales from the nano- to micro- and meso-level. Therefore, multi-scale approaches are essential for a better understanding of mechanical properties and fracture in particular. This volume includes various examples of fracture analyses at the micro- and meso-level. The book presents models accompanied by reliable experiments and explains how these experiments are performed. It also provides numerous examples of test methods and requirements for evaluating quasi-brittle materials. More importantly, it proposes a new modeling approach based on multiscale interaction potential and examines the related experimental challenges facing research engineers and building professionals. The book’s comprehensive coverage is poised to encourage new initiatives for overcoming the difficulties encountered when performing fracture experiments on cement at the micro-size/scale and smaller. The author demonstrates how the obtained results can fit into the larger picture of the material science of concrete—particularly the design of new high-performance concrete materials which can be put to good use in the development of efficient and durable structures.
Download or read book Fracture Mechanics written by Chin-Teh Sun and published by Academic Press. This book was released on 2011-10-14 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: From a leading expert in fracture mechanics, this text provides new approaches and new applications to advance the understanding of crack formation and propagation.
Download or read book Fracture Mechanics written by Chin-Teh Sun and published by Academic Press. This book was released on 2011-10-04 with total page 337 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fracture Mechanics covers classical and modern methods and introduce new/unique techniques, making this text an important resource for anyone involved in the study or application of fracture mechanics. Using insights from leading experts in fracture mechanics, it provides new approaches and new applications to advance the understanding of crack initiation and propagation. With a concise and easily understood mathematical treatment of crack tip fields, this book provides the basis for applying fracture mechanics in solving practical problems. It features a unique coverage of bi-material interfacial cracks, with applications to commercially important areas of composite materials, layered structures, and microelectronic packaging. A full chapter is devoted to the cohesive zone model approach, which has been extensively used in recent years to simulate crack propagation. A unified discussion of fracture criteria involving nonlinear/plastic deformations is also provided. The book is an invaluable resource for mechanical, aerospace, civil, and biomedical engineers in the field of mechanics as well as for graduate students and researchers studying mechanics. Concise and easily understood mathematical treatment of crack tip fields (chapter 3) provides the basis for applying fracture mechanics in solving practical problems Unique coverage of bi-material interfacial cracks (chapter 8), with applications to commercially important areas of composite materials, layered structures, and microelectronic packaging A full chapter (chapter 9) on the cohesive zone model approach, which has been extensively used in recent years to simulate crack propagation A unified discussion of fracture criteria involving nonlinear/plastic deformations
Download or read book Molecular Orbitals and the Atomistics of Fracture written by M. E. Eberhardt and published by . This book was released on 1981 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: Self-consistent-field Xalpha scattered-wave (SCF-Xa-SW) cluster molecular-orbital models have been constructed for grain-boundary embrittlement of metals. Two specific examples are presented: (1) the embrittlement of nickel by sulfur and (2) the embrittlement of iron by hydrogen. (Author).
Download or read book An Atomistic Approach to Fracture Mechanics written by Norman H. Macmillan and published by . This book was released on 1972 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: It is possible that accurate atomic models of the regions at the tips of cracks in stressed materials could provide greater insight into the fundamentals of the fracture process than has been obtained from the continuum models employed hitherto. Accordingly, a study has been made of the problems of constructing such atomic models. Several common interatomic potentials have been examined to determine their suitability for such an application, and numerical methods of obtaining crack tip structures from the most suitable of these have been developed and programmed. A few preliminary crack tips have been modelled to demonstrate the validity of the atomistic approach. (Author).
