Download or read book Quantifying the Influence of Twin Boundaries on the Deformation of Nanocrystalline Copper Using Atomistic Simulations written by and published by . This book was released on 2014 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the past decade, numerous efforts have sought to understand the influence of twin boundaries on the behavior of polycrystalline materials. Early results suggested that twin boundaries within nanocrystalline face-centered cubic metals have a considerable effect on material behavior by altering the activated deformation mechanisms. In this work, we employ molecular dynamics simulations to elucidate the role of twin boundaries on the deformation of 100 columnar nanocrystalline copper at room temperature under uniaxial strain. We leverage non-local kinematic metrics, formulated from continuum mechanics theory, to compute atomically-resolved rotational and strain fields during plastic deformation. These results are then utilized to compute the distribution of various nanoscale mechanisms during straining, and quantitatively resolve their contribution to the total strain accommodation within the microstructure, highlighting the fundamental role of twin boundaries. Our results show that nanoscale twins influence nanocrystalline copper by altering the cooperation of fundamental deformation mechanisms and their contributed role in strain accommodation, and we present new methods for extracting useful information from atomistic simulations. The simulation results suggest a tension-compression asymmetry in the distribution of deformation mechanisms and strain accommodation by either dislocations or twin boundary mechanisms. In highly twinned microstructures, twin boundary migration can become a significant deformation mode, in comparison to lattice dislocation plasticity in non-twinned columnar microstructures, especially during compression.
Download or read book Multiscale Materials Modeling for Nanomechanics written by Christopher R. Weinberger and published by Springer. This book was released on 2016-08-30 with total page 554 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents a unique combination of chapters that together provide a practical introduction to multiscale modeling applied to nanoscale materials mechanics. The goal of this book is to present a balanced treatment of both the theory of the methodology, as well as some practical aspects of conducting the simulations and models. The first half of the book covers some fundamental modeling and simulation techniques ranging from ab-inito methods to the continuum scale. Included in this set of methods are several different concurrent multiscale methods for bridging time and length scales applicable to mechanics at the nanoscale regime. The second half of the book presents a range of case studies from a varied selection of research groups focusing either on a the application of multiscale modeling to a specific nanomaterial, or novel analysis techniques aimed at exploring nanomechanics. Readers are also directed to helpful sites and other resources throughout the book where the simulation codes and methodologies discussed herein can be accessed. Emphasis on the practicality of the detailed techniques is especially felt in the latter half of the book, which is dedicated to specific examples to study nanomechanics and multiscale materials behavior. An instructive avenue for learning how to effectively apply these simulation tools to solve nanomechanics problems is to study previous endeavors. Therefore, each chapter is written by a unique team of experts who have used multiscale materials modeling to solve a practical nanomechanics problem. These chapters provide an extensive picture of the multiscale materials landscape from problem statement through the final results and outlook, providing readers with a roadmap for incorporating these techniques into their own research.
Download or read book Atomistic Simulation Studies of Grain Boundary Segregation and Strengthening Mechanisms in Nanocrystalline Nanotwinned Silver Copper Alloys written by Xing Ke and published by . This book was released on 2019 with total page 314 pages. Available in PDF, EPUB and Kindle. Book excerpt: Silver (Ag) is a precious metal with a low stacking fault energy that is known to form copious nanoscale coherent twin boundaries during magnetron sputtering synthesis. Nanotwinned Ag metals are potentially attractive for creating new interface-dominated nanomaterials with unprecedented mechanical and physical properties. Grain-boundary segregation of solute elements has been found to increase the stability of interfaces and hardness of nanocrystalline metals. However, heavily alloying inevitably complicates the underlying deformation mechanisms due to the hardening effects of solutes, or a change of stacking fault energies in Ag caused by alloying. For the above reasons, we developed a microalloying (or doping) strategy by carefully selecting Cu as the primary impurity--a solute that is predicted to have no solid-solution strengthening effect in Ag when its content is below 3.0 wt.%. Neither will Cu affect the stacking fault energy of Ag at a concentration
Download or read book Shear Deformation of Amorphous and Nanocrystalline Copper Microstructures Via Atomistic Simulation written by David R. Gandy and published by . This book was released on 2007 with total page 24 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the well-known Hall-Petch behavior, yield and flow stresses in polycrystalline metals increase with a decrease in grain size. As grain size continues to decrease, mechanical strength peaks. As grain size further decreases, mechanical strength begins to decrease. As grain size approaches zero, the total structure is composed of an increasingly high percentage of grain boundaries, which exhibit the properties of an amorphous structure. Molecular dynamics simulations, with the goal of exploring this behavior, were performed on nanocrystalline and amorphous microstructures using the embedded atom potential developed by Mishin et al. A 0.2 shear strain was applied to each of the nanocrystalline and amorphous samples. From these simulations, we have observed the inverse Hall-Petch behavior of nanocrystalline structures. We have also shown that the amorphous structure as zero grain size is reasonable as the limiting case for the inverse Hall-Petch trends in nanocrystalline structures.
Download or read book The Inverse Hall Petch Problem written by David J. Fisher and published by Materials Research Forum LLC. This book was released on 2019-08-20 with total page 152 pages. Available in PDF, EPUB and Kindle. Book excerpt: The book reviews the Hall-Petch law, one of the most useful equations of materials science, and the reverse or inverse Hall-Petch relation, which is particular important for controlling the strength of nanocrystalline materials. Theoretical models, experimental data and practical aspects are discussed, making reference to a total of 396 original resources with their direct web link for in-depth reading.
Download or read book NIC Symposium 2010 written by John-von-Neumann-Institut für Computing (Jülich) and published by Forschungszentrum Jülich. This book was released on 2010 with total page 411 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Atomistic Simulations Based Study of Nanoscale Deformation in Copper written by Ajith K. Ukwattage and published by . This book was released on 2014 with total page 186 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Crystal Plasticity Finite Element Methods written by Franz Roters and published by John Wiley & Sons. This book was released on 2011-08-04 with total page 188 pages. Available in PDF, EPUB and Kindle. Book excerpt: Written by the leading experts in computational materials science, this handy reference concisely reviews the most important aspects of plasticity modeling: constitutive laws, phase transformations, texture methods, continuum approaches and damage mechanisms. As a result, it provides the knowledge needed to avoid failures in critical systems udner mechanical load. With its various application examples to micro- and macrostructure mechanics, this is an invaluable resource for mechanical engineers as well as for researchers wanting to improve on this method and extend its outreach.
Download or read book The Plaston Concept written by Isao Tanaka and published by Springer. This book was released on 2022-02-28 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book presents the novel concept of plaston, which accounts for the high ductility or large plastic deformation of emerging high-performance structural materials, including bulk nanostructured metals, hetero-nanostructured materials, metallic glasses, intermetallics, and ceramics.The book describes simulation results of the collective atomic motion associated with plaston, by computational tools such as first-principle methods with predictive performance and large-scale atom-dynamics calculations. Multi-scale analyses with state-of-the art analytical tools nano/micro pillar deformation and nano-indentation experiments are also described. Finally, through collaborative efforts of experimental and computational work, examples of rational design and development of new structural materials are given, based on accurate understanding of deformation and fracture phenomena.This publication provides a valuable contribution to the field of structural materials research.
Download or read book Classical And Quantum Dynamics In Condensed Phase Simulations Proceedings Of The International School Of Physics written by Bruce J Berne and published by World Scientific. This book was released on 1998-06-17 with total page 881 pages. Available in PDF, EPUB and Kindle. Book excerpt: The school held at Villa Marigola, Lerici, Italy, in July 1997 was very much an educational experiment aimed not just at teaching a new generation of students the latest developments in computer simulation methods and theory, but also at bringing together researchers from the condensed matter computer simulation community, the biophysical chemistry community and the quantum dynamics community to confront the shared problem: the development of methods to treat the dynamics of quantum condensed phase systems.This volume collects the lectures delivered there. Due to the focus of the school, the contributions divide along natural lines into two broad groups: (1) the most sophisticated forms of the art of computer simulation, including biased phase space sampling schemes, methods which address the multiplicity of time scales in condensed phase problems, and static equilibrium methods for treating quantum systems; (2) the contributions on quantum dynamics, including methods for mixing quantum and classical dynamics in condensed phase simulations and methods capable of treating all degrees of freedom quantum-mechanically.
Download or read book Handbook of Materials Modeling written by Sidney Yip and published by Springer Science & Business Media. This book was released on 2007-11-17 with total page 2903 pages. Available in PDF, EPUB and Kindle. Book excerpt: The first reference of its kind in the rapidly emerging field of computational approachs to materials research, this is a compendium of perspective-providing and topical articles written to inform students and non-specialists of the current status and capabilities of modelling and simulation. From the standpoint of methodology, the development follows a multiscale approach with emphasis on electronic-structure, atomistic, and mesoscale methods, as well as mathematical analysis and rate processes. Basic models are treated across traditional disciplines, not only in the discussion of methods but also in chapters on crystal defects, microstructure, fluids, polymers and soft matter. Written by authors who are actively participating in the current development, this collection of 150 articles has the breadth and depth to be a major contributor toward defining the field of computational materials. In addition, there are 40 commentaries by highly respected researchers, presenting various views that should interest the future generations of the community. Subject Editors: Martin Bazant, MIT; Bruce Boghosian, Tufts University; Richard Catlow, Royal Institution; Long-Qing Chen, Pennsylvania State University; William Curtin, Brown University; Tomas Diaz de la Rubia, Lawrence Livermore National Laboratory; Nicolas Hadjiconstantinou, MIT; Mark F. Horstemeyer, Mississippi State University; Efthimios Kaxiras, Harvard University; L. Mahadevan, Harvard University; Dimitrios Maroudas, University of Massachusetts; Nicola Marzari, MIT; Horia Metiu, University of California Santa Barbara; Gregory C. Rutledge, MIT; David J. Srolovitz, Princeton University; Bernhardt L. Trout, MIT; Dieter Wolf, Argonne National Laboratory.
Download or read book Handbook of the Physicochemical Properties of the Elements written by Gregory V. Samsonov and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 953 pages. Available in PDF, EPUB and Kindle. Book excerpt: The American edition of this handbook contains concise informa tion on the basic physical properties of the elements and on their chem ical characteristics. In general, the data selected for inclusion in the handbook are those which either agree well with calculated data (in those cases where calculations could be carried out) or satisfy various correlations, particularly those based on concepts of the distribution of valence electrons of isolated atoms in the formation of a condensed state, as electrons localized at atomic ions in the form of energetically stable configurations, and as nonlocalized electrons. The Russian edition was published in the USSR in 1965, and new or previously omitted data have been added to all the sections of the present edition. In addition, the authors have considered it necessary to include a series of new sections. Thus, a new table has been included, "Electronic Configurations and Ground States of Free Atoms and Their Ions," since, in the ionization of some atoms (particularly for transition metals), the electrons are not always abstracted from the outer shell, and, consequently, calculation of the ground state (electron energy level) using the usual vector model does not give a direct result. The ground states are obtained experimentally and the table contains the corresponding data on the configurations and states of triply-ionized atoms (which is usually sufficient).
Download or read book Proceedings of the 3rd Conference on Physical Modeling for Virtual Manufacturing Systems and Processes written by Jan C. Aurich and published by Springer Nature. This book was released on 2023-07-10 with total page 305 pages. Available in PDF, EPUB and Kindle. Book excerpt: This is an open access book reporting the results of nine years research of the International Research Training Group (IRTG) 2057, funded by the German Research Foundation (DFG). The IRTG is a joint venture between the TU Kaiserslautern, the University of California Berkeley, and University of California Davis. The book is content-driven mainly by two disciplines: engineering and computer science. Through the application of scientific knowledge and advanced computer-based methods in conjunction with physical models on a level unrealized in the past, technologies and methods are promoted, which can be used for planning and optimization of manufacturing systems and processes. As a result, fundamental understanding as well as extensive systems, tools and computational algorithms, which significantly improve the integration of advanced computational methods for solving problems of manufacturing systems and processes will be available. This open access book is of interest to any researcher dealing with process and factory planning in manufacturing, like for cutting and additive manufacturing.
Download or read book Heterostructured Materials written by Xiaolei Wu and published by CRC Press. This book was released on 2021-11-24 with total page 796 pages. Available in PDF, EPUB and Kindle. Book excerpt: Heterostructured (HS) materials represent an emerging class of materials that are expected to become a major research field for the communities of materials, mechanics, and physics in the next couple of decades. One of the biggest advantages of HS materials is that they can be produced by large-scale industrial facilities and technologies and therefore can be commercialized without the scaling up and high-cost barriers that are often encountered by other advanced materials. This book collects recent papers on the progress in the field of HS materials, especially their fundamental physics. The papers are arranged in a sequence of chapters that will help new researchers entering the field to have a quick and comprehensive understanding of HS materials, including the fundamentals and recent progress in their processing, characterization, and properties.
Download or read book Dislocations Mesoscale Simulations and Plastic Flow written by Ladislas Kubin and published by OUP Oxford. This book was released on 2013-04-18 with total page 320 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the past twenty years, new experimental approaches, improved models and progress in simulation techniques brought new insights into long-standing issues concerning dislocation-based plasticity in crystalline materials. During this period, three-dimensional dislocation dynamics simulations appeared and reached maturity. Their objectives are to unravel the relation between individual and collective dislocation processes at the mesoscale, to establish connections with atom-scale studies of dislocation core properties and to bridge, in combination with modelling, the gap between defect properties and phenomenological continuum models for plastic flow. Dislocation dynamics simulations are becoming accessible to a wide range of users. This book presents to students and researchers in materials science and mechanical engineering a comprehensive coverage of the physical body of knowledge on which they are based. It includes classical studies, which are too often ignored, recent experimental and theoretical advances, as well as a discussion of selected applications on various topics.
Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1991 with total page 1460 pages. Available in PDF, EPUB and Kindle. Book excerpt: Lists citations with abstracts for aerospace related reports obtained from world wide sources and announces documents that have recently been entered into the NASA Scientific and Technical Information Database.
Download or read book Metals Abstracts written by and published by . This book was released on 1998 with total page 1076 pages. Available in PDF, EPUB and Kindle. Book excerpt:
