Read Books Online and Download eBooks, EPub, PDF, Mobi, Kindle, Text Full Free.
Effect Of Stress Triaxiality On Void Growth In Dynamic Fracture Of Metals
Download Effect Of Stress Triaxiality On Void Growth In Dynamic Fracture Of Metals full books in PDF, epub, and Kindle. Read online Effect Of Stress Triaxiality On Void Growth In Dynamic Fracture Of Metals ebook anywhere anytime directly on your device. Fast Download speed and no annoying ads. We cannot guarantee that every ebooks is available!
Book Synopsis Effect of Stress-triaxiality on Void Growth in Dynamic Fracture of Metals by :
Download or read book Effect of Stress-triaxiality on Void Growth in Dynamic Fracture of Metals written by and published by . This book was released on 2003 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt: The effect of stress-triaxiality on growth of a void in a three dimensional single-crystal face-centered-cubic (FCC) lattice has been studied. Molecular dynamics (MD) simulations using an embedded-atom (EAM) potential for copper have been performed at room temperature and using strain controlling with high strain rates ranging from 107/sec to 101°/sec. Strain-rates of these magnitudes can be studied experimentally, e.g. using shock waves induced by laser ablation. Void growth has been simulated in three different conditions, namely uniaxial, biaxial, and triaxial expansion. The response of the system in the three cases have been compared in terms of the void growth rate, the detailed void shape evolution, and the stress-strain behavior including the development of plastic strain. Also macroscopic observables as plastic work and porosity have been computed from the atomistic level. The stress thresholds for void growth are found to be comparable with spall strength values determined by dynamic fracture experiments. The conventional macroscopic assumption that the mean plastic strain results from the growth of the void is validated. The evolution of the system in the uniaxial case is found to exhibit four different regimes: elastic expansion; plastic yielding, when the mean stress is nearly constant, but the stress-triaxiality increases rapidly together with exponential growth of the void; saturation of the stress-triaxiality; and finally the failure.
Book Synopsis Strain-hardening and Interaction Effects on the Growth of Voids in Ductile Fracture by : Dennis Michael Tracey
Download or read book Strain-hardening and Interaction Effects on the Growth of Voids in Ductile Fracture written by Dennis Michael Tracey and published by . This book was released on 1968 with total page 36 pages. Available in PDF, EPUB and Kindle. Book excerpt: The growth and coalescence of voids is a common mechanism of fracture in ductile materials. Analytical work on the problem to date has dealt mainly with isolated voids in perfectly plastic materials, so that strain hardening and interactions between neighboring voids have been neglected. These features of void growth are examined here, but only for a simple geometrical configuration. In particular, the growth of single infinitely long cylindrical voids in bodies of rigid-plastic, strain-hardening material is considered. Bodies with both finite and infinite dimensions normal to the void surface are included in the analysis. The exact relation among the pertinent variables: transverse stress, axial strain, hardening coefficient, void strain and void growth rate is presented. Solution via a bounding technique is given for two general cases. The first case is that of an imposed constant void growth rate and the second case is an imposed constant transverse stress. The results show a decelerating effect of hardening on void growth. Application to the ductile fracture problem of void growth in the neck of a tensile specimen demonstrates the accelerating effect of void growth due to interactions between voids. (Author).
Book Synopsis Void Growth and Coalescence in Dynamic Fracture from the Atomistic Level by :
Download or read book Void Growth and Coalescence in Dynamic Fracture from the Atomistic Level written by and published by . This book was released on 2010 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important example of multiscale material response is the fracture of ductile solids. In the process of ductile fracture, voids nucleate, grow and coalesce, and it is this linking process that creates the fracture. Ductile fracture has typically been modeled at the continuum level, in a variety of models that may or may not model voids explicitly. Previously we have studied the plasticity associated with void growth in fcc metals, focusing on copper. In the work discussed here we examine void growth in single crystal and polycrystalline body-centered cubic (bcc) metals (V, Nb, Ta, Mo and W) subjected to tension at a high rate and high triaxiality. Large-scale atomistic models provide detailed information on void nucleation and growth and the plasticity generated as voids coalesce, based solely on the constitutive properties inherent in the interatomic forces. The details of the plasticity may be used to inform dislocation dynamics and continuum plasticity models in order to develop models that scale beyond the nanoscale. We also discuss concurrent multiscale modeling of void growth using Coarse-Grained Molecular Dynamics.
Book Synopsis Stress Field Effects on Dynamic Fracture by : Ian M. Fyfe
Download or read book Stress Field Effects on Dynamic Fracture written by Ian M. Fyfe and published by . This book was released on 1981 with total page 19 pages. Available in PDF, EPUB and Kindle. Book excerpt: The introduction of inertia terms in the theoretical model of thin ring expansion showed that the classical plastic instability concepts, defined in terms of the local strain in the necking region, no longer applied. The introduction of the role of void growth in triggering local necking, through the recently proposed constitutive equation for porous plastic materials allowed this difficulty to be overcome. A criterion based on a critical void volume fraction provided the alternative means to predict failure. This theory was applied to number of configurations (thin ring, thick plate and thick cylinder) under high strain rate loading conditions, and the theoretical results were found to compare favorably with experimental values.
Book Synopsis Advances in Fracture Research: Brittle fracture ; Ductile fracture ; Dynamic fracture by :
Download or read book Advances in Fracture Research: Brittle fracture ; Ductile fracture ; Dynamic fracture written by and published by . This book was released on 1989 with total page 920 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis A Void Growth Model Relating Fracture Toughness and Constraint by : TC. Miller
Download or read book A Void Growth Model Relating Fracture Toughness and Constraint written by TC. Miller and published by . This book was released on 1994 with total page 21 pages. Available in PDF, EPUB and Kindle. Book excerpt: Loading of a metal results in the nucleation of voids around particles. Further deformation results in void growth and coalescence. This work combines mathematical models for void nucleation, growth, and coalescence into a simulation of a ductile fracture to examine the effects of stress triaxiality and constraint loss on ductile fracture.
Book Synopsis Dynamics of Fracture by : N. Morozov
Download or read book Dynamics of Fracture written by N. Morozov and published by Springer Science & Business Media. This book was released on 2000-03-06 with total page 112 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this book a new phenomenological approach to brittle medium fracture initiation under shock pulses is developped. It provides an opportunity to estimate fracture of media with and without macrodefects. A qualitative explanation is thus obtained for a number of principally important effects of high-speed dynamic fracture that cannot be clarified within the framework of previous approaches. It is possible to apply this new strategy to resolve applied problems of disintegration, erosion, and dynamic strength determination of structural materials. Specialists can use the methods described to determine critical characteristics of dynamic strength and optimal effective fracture conditions for rigid bodies. This book can also be used as a special educational course on deformation of materials and constructions, and fracture mechanics.
Book Synopsis Developments in Fracture Mechanics: The mechanics and mechanisms of fracture in metals by : G. G. Chell
Download or read book Developments in Fracture Mechanics: The mechanics and mechanisms of fracture in metals written by G. G. Chell and published by Elsevier Science & Technology. This book was released on 1981 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dynamic fracture written by M.L. Williams and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 187 pages. Available in PDF, EPUB and Kindle. Book excerpt: From time to time the International Journal of Fracture has presented matters thought to be of special interest to its readers. In previous special issues (December 1980 and April 1981), Dr H.W. Liu as Guest Editor presented a series of review papers dealing with fatigue processes and characteristics in metals and non-metals. Continuing this policy, which is consistent with our stated objectives, a second review dealing with time depen dence in the fracture process, including the effect of material inertia but essentially excluding very strong shock effects in solids, has been assembled under the generic term "dynamic fracture". We hope that the ensuing state-of-the-art review will yield an instructive and timely product which readers will find useful. To assist us in presenting this subject, we have prevailed upon a well-known worker in dynamic fracture, Dr W.G. Knauss, Professor of Aeronautics and Applied Mechanics, California Institute of Technology to act as Guest Editor for this special double issue. On behalf of the editors and publisher, I wish to express our indebtedness to Professor Knauss and his invited authors for undertaking this special effort.
Book Synopsis Ductile Fracture and Ductility by : Bradley Dodd
Download or read book Ductile Fracture and Ductility written by Bradley Dodd and published by Academic Press. This book was released on 1987 with total page 328 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Constraint Effects in Fracture by : E. M. Hackett
Download or read book Constraint Effects in Fracture written by E. M. Hackett and published by ASTM International. This book was released on 1993 with total page 514 pages. Available in PDF, EPUB and Kindle. Book excerpt: Papers presented at the symposium on [title] held in Indianapolis, Indiana, May 1991, provide a framework for quantifying constraint effects in terms of both continuum mechanics and micro-mechanical modeling approaches. Such a framework is useful in establishing accurate predictions of the fracture
Book Synopsis Advances in Fracture and Damage Mechanics VII by : H.S. Lee
Download or read book Advances in Fracture and Damage Mechanics VII written by H.S. Lee and published by Trans Tech Publications Ltd. This book was released on 2008-07-02 with total page 922 pages. Available in PDF, EPUB and Kindle. Book excerpt: Volume is indexed by Thomson Reuters CPCI-S (WoS). This volume is made up of contributions from researchers in 22 countries. It aims to promote exchange of the latest experimental and theoretical results on structural integrity, durability and failure analysis; with the emphasis on fracture and damage mechanics.
Book Synopsis Molecular Dynamics Study of Void Growth and Dislocations in Dynamic Fracture of FCC and BCC Metals by :
Download or read book Molecular Dynamics Study of Void Growth and Dislocations in Dynamic Fracture of FCC and BCC Metals written by and published by . This book was released on 2003 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: Void growth with concomitant dislocation formation has been studied in single crystal face-centered-cubic and body-centered-cubic metals using molecular dynamics method with Embedded-Atom and Finnis-Sinclair potentials for copper and tantalum, respectively. We have concentrated on the quantitative analysis of the void shape evolution, on the structure of dislocations, which emerge from the void, and on the continuum measures such as plastic strain. The effects of strain-rate, differences between lattice structures, and loading conditions as uniaxial, biaxial, and triaxial expansion on the shape of the void and on the dislocations have been investigated.
Book Synopsis Studies on Strain Localization, Ductile Fracture and Damage in Structural Metals by : Yazhi Zhu
Download or read book Studies on Strain Localization, Ductile Fracture and Damage in Structural Metals written by Yazhi Zhu and published by . This book was released on 2017 with total page 666 pages. Available in PDF, EPUB and Kindle. Book excerpt: One of the most important limit states in structural metals is ductile fracture, and the prediction of ductile fracture is of great importance in many engineering applications. The overall objective of the research reported in this dissertation is to advance the understanding and modeling of ductile fracture in metals. This research addresses three main issues: micromechanical modeling of ductile fracture, the development of a micromechanics-based ductile fracture model and its numerical implementation, and a numerical investigation of geometry and damage induced strain localization based on a nonlocal formulation. It has long been recognized that stress triaxiality is a key parameter affecting initiation of ductile fracture. More recently, shear stress has been identified as another important parameter, in addition to stress triaxiality, that influences the process of ductile fracture. In this research, a micromechanics-based model is proposed for predicting initiation of ductile fracture that couples both stress triaxiality and shear stress. The new model is based on a combination of the existing Rice-Tracey and modified maximum shear stress models. The new model is applied to construct the fracture locus of different types of metal alloys and is used to predict fracture initiation by numerical tools. The predicted results are in good agreement with experimental data reported in literature that covers a wide range of triaxialities and shear stress. Another portion of this research, within the framework of micromechanics, investigated the effect of combined normal and shear stress components on micro-void evolution and material behavior. This work involved finite element modeling of a cubic unit cell associated with a spherical void. The results show that the void growth process and macroscopic stress-strain response is highly dependent on the shear stress component. At different ranges of triaxialities, and with different void growth and coalescence mechanisms, shear stress has an important effect on the ductile fracture process. Numerical modeling of strain localization in ductile metals based on standard continuum mechanics exhibits non-convergent mesh sensitivity. This issue is addressed in the final portion of this research. A one-dimensional model based on the nonlocal theory is proposed to analyze geometry-induced strain localization, i.e., necking in structural metals. A nonlocal continuum damage model using the same enhanced continuum law is developed to deal with the damage induced strain localization in metals. Both models provide encouraging performance in eliminating the non-convergent mesh sensitivity problem. Such improved strain localization modeling techniques show potential to be useful for further exploration of ductile fracture phenomena.
Book Synopsis Studies in Large Plastic Flow and Fracture by : Percy Williams Bridgman
Download or read book Studies in Large Plastic Flow and Fracture written by Percy Williams Bridgman and published by Cambridge : Harvard University Press. This book was released on 1964 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Advances in Heterogeneous Material Mechanics 2011 by : Jinghong Fan
Download or read book Advances in Heterogeneous Material Mechanics 2011 written by Jinghong Fan and published by DEStech Publications, Inc. This book was released on 2011 with total page 1205 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Multiscale Methods written by Jacob Fish and published by Oxford University Press. This book was released on 2010 with total page 631 pages. Available in PDF, EPUB and Kindle. Book excerpt: Small scale features and processes occurring at nanometer and femtosecond scales have a profound impact on what happens at a larger scale and over an extensive period of time. The primary objective of this volume is to reflect the state-of-the-art in multiscale mathematics, modeling, and simulations and to address the following barriers: What is the information that needs to be transferred from one model or scale to another and what physical principles must be satisfied during thetransfer of information? What are the optimal ways to achieve such transfer of information? How can variability of physical parameters at multiple scales be quantified and how can it be accounted for to ensure design robustness?The multiscale approaches in space and time presented in this volume are grouped into two main categories: information-passing and concurrent. In the concurrent approaches various scales are simultaneously resolved, whereas in the information-passing methods the fine scale is modeled and its gross response is infused into the continuum scale. The issue of reliability of multiscale modeling and simulation tools which focus on a hierarchy of multiscale models and an a posteriori model of errorestimation including uncertainty quantification, is discussed in several chapters. Component software that can be effectively combined to address a wide range of multiscale simulations is also described. Applications range from advanced materials to nanoelectromechanical systems (NEMS), biologicalsystems, and nanoporous catalysts where physical phenomena operates across 12 orders of magnitude in time scales and 10 orders of magnitude in spatial scales.This volume is a valuable reference book for scientists, engineers and graduate students practicing in traditional engineering and science disciplines as well as in emerging fields of nanotechnology, biotechnology, microelectronics and energy.
