Download or read book Advancing Numerical Simulation Tools for Ductile Fracture in Thin Metal Plates written by Rasmus Grau Andersen and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Ductile Fracture in Metal Forming written by Kazutake Komori and published by Academic Press. This book was released on 2019-10-11 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ductile Fracture in Metal Forming: Modeling and Simulation examines the current understanding of the mechanics and physics of ductile fracture in metal forming processes while also providing an approach to micromechanical ductile fracture prediction that can be applied to all metal forming processes. Starting with an overview of different ductile fracture scenarios, the book then goes on to explain modeling techniques that predict a range of mechanical phenomena that can lead to ductile fracture. The challenges in creating micromechanical models are addressed alongside methods of applying these models to several common metal forming processes. This book is suitable for researchers working in mechanics of materials, metal forming, mechanical metallurgy, and plasticity. Engineers in R&D industries involved in metal forming such as manufacturing, aerospace, and automation will also find the book very useful. Explains innovative micromechanical modeling techniques for a variety of material behaviors Examines how these models can be applied to metal forming processes in practice, including blanking, arrowed cracks in drawing, and surface cracks in upset forging Provides a thorough examination of both macroscopic and microscopic ductile fracture theory

Download or read book Damage Mechanics in Metal Forming written by Khemais Saanouni and published by John Wiley & Sons. This book was released on 2013-02-04 with total page 397 pages. Available in PDF, EPUB and Kindle. Book excerpt: The aim of this book is to summarize the current most effective methods for modeling, simulating, and optimizing metal forming processes, and to present the main features of new, innovative methods currently being developed which will no doubt be the industrial tools of tomorrow. It discusses damage (or defect) prediction in virtual metal forming, using advanced multiphysical and multiscale fully coupled constitutive equations. Theoretical formulation, numerical aspects as well as application to various sheet and bulk metal forming are presented in detail. Virtual metal forming is nowadays inescapable when looking to optimize numerically various metal forming processes in order to design advanced mechanical components. To do this, highly predictive constitutive equations accounting for the full coupling between various physical phenomena at various scales under large deformation including the ductile damage occurrence are required. In addition, fully 3D adaptive numerical methods related to time and space discretization are required in order to solve accurately the associated initial and boundary value problems. This book focuses on these two main and complementary aspects with application to a wide range of metal forming and machining processes. Contents 1. Elements of Continuum Mechanics and Thermodynamics. 2. Thermomechanically-Consistent Modeling of the Metals Behavior with Ductile Damage. 3. Numerical Methods for Solving Metal Forming Problems. 4. Application to Virtual Metal Forming.

Download or read book Development of Numerical Approaches to Predict Ductile and Cleavage Fracture of Structural Materials written by Guihua Zhang and published by . This book was released on 2007 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Numerical simulations mainly using finite element method are playing a more and more important role in prediction of fracture-induced failure for high performance structure. This thesis seeks to develop numerical approaches to predict ductile and cleavage fracture in structural materials. For ductile fracture, the discrete void approach reveals the failure mechanisms explicitly and is used to study the trends of fracture toughness. The porous continuum approach provides an effective means to predict extensive crack propagation. We consider the occurrence of material failure (void coalescence) as when localization of plastic flow takes place in the inter-void ligament and obtain the failure criterion as a function of the stress triaxiality ratio and the Lode angle. The Gologanu-Leblond Devaux (GLD) model, which accounts for the evolution of both void volume and void shape, is used to describe the porous placticity behavior and is implemented into ABAQUS via a user subroutine. Numerical simulations are performed to predict extensive crack growth in ductile solids for a thin aluminum 2024-T3 plate and verified by successful predication of crack extension in various specimens, including the multiple site damage speciments. The effect of stress triaxiality and Lode angle is further analyzed and the Xue-Wierzbicki fracture locus is employed as a criterion for void colescence. Combination of GLD model and X-W fracture locus is then applied to a DH-36 steel with specimens experiencing a wide range of stress triaxiality and Lode angles at failure. The numerical simulation results agree very well with the experimental results. For cleavage fracture, a modified three parameter Weibull stress model is proposed and used to predict the fracture of A508 steel at three different temperatures. By integrating the Weibull stress model over the plastic process zone, the failure probability can be obtained and comparison is made with the experiment result. Issues addressed include calibration of the model parameters, introduction of a threshold parameter, dependencies of the model parameters on temperature, plastic strain effect and crack tip triaxiality effect, etc."--Abstract.

Download or read book Advanced Methods in Materials Processing Defects written by M. Predeleanu and published by Elsevier. This book was released on 1997-06-18 with total page 439 pages. Available in PDF, EPUB and Kindle. Book excerpt: This collection of papers focus on advanced methods for predicting and avoiding the occurrence of defects in manufactured products. A new feature is included, namely, the influence of the processing-induced defects on the integrity of structures. The following topics are developed: damage modeling; damage evaluation and rupture; strain localization and instability analysis; formability characterization; prediction of shape inaccuracies; influence of defects on structural integrity. The main manufacturing operations are covered and various materials are examined, such as new and conventional metal alloys, ceramics, polymers and composites.

Download or read book Ductile Fracture Analysis in a Steel Plate by Cohesive Zone Modeling written by Tayyebe Seif and published by . This book was released on 2014 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: There are several theories used to describe fracture process including Linear Elastic Fracture Mechanics (LEFM), Elastic-Plastic Fracture Mechanics (EPFM), and Cohesive Zone Models (CZM), which allow for development of predictive capabilities. The main disadvantage of LEFM and EPFM techniques is that only structures with an initial crack can be modeled. Other drawbacks of these techniques are geometry dependence and validity limits. In contrast, CZM can simulate fracture in any structures, with or without a crack. CZM is not confined to a class of materials, but it can be used for arbitrary materials. In this research, the CZM was used to numerically simulate crack initiation and growth in steel plates. Within the CZM, material separation (i.e. damage of the structure) is described by interface elements, which open irreversibly and lose their stiffness at failure, causing the continuum elements to be disconnected. Numerical simulation of tensile tests was conducted to determine and validate the cohesive parameters and then these parameters were used for modeling mode I fracture in steel plates. It was shown that the cohesive model is capable of simulating ductile fracture in cases where the crack path is not known in advance and the crack can evolve anywhere in the specimen.

Download or read book Advanced High Strength Steel And Press Hardening Proceedings Of The 2nd International Conference Ichsu2015 written by Yisheng Zhang and published by World Scientific. This book was released on 2016-03-11 with total page 753 pages. Available in PDF, EPUB and Kindle. Book excerpt: This proceedings brings together one hundred and ten selected papers presented at the 2nd International Conference on Advanced High Strength Steel and Press Hardening (ICHSU2015), which was held in Changsha, China, during October 15-18, 2015.To satisfy the increasingly urgent requirement of reducing the weight of vehicle structures and increasing passenger safety, ICHSU2015 provided an excellent international platform for researchers to share their knowledge and results in theory, methodology and applications of advanced high strength steel and press hardening technology.This conference aroused great interests and attentions from domestic and foreign researchers in hot stamping field. Experts in this field from Australia, China, Germany and Sweden, contributed to the collection of research results and developments. The papers cover almost all the current topics of advanced high strength steel and press hardening technology.

Download or read book NUMISHEET 2022 written by Kaan Inal and published by Springer Nature. This book was released on 2022-06-30 with total page 941 pages. Available in PDF, EPUB and Kindle. Book excerpt: The NUMISHEET conference series is the most significant international conference on the area of the numerical simulation of sheet metal forming processes. It gathers the most prominent experts in numerical methods in sheet forming processes and is an outstanding forum for the exchange of ideas and for the discussion of technologies related to sheet metal forming processes. Topics covered in this volume include but are not limited to the following: Materials Modeling and Experimental Testing Methods Friction and Contact Formability, Necking, and Fracture Instabilities and Surface Defects Fracture and Damage Numerical Methods Springback Incremental Sheet Forming Roll Forming Innovative Forming Methods Product and Process Design and Optimization

Download or read book Dynamic Behavior of Materials Volume 1 written by Bo Song and published by Springer. This book was released on 2014-08-08 with total page 386 pages. Available in PDF, EPUB and Kindle. Book excerpt: Dynamic Behavior of Materials, Volume 1: Proceedings of the 2014 Annual Conference on Experimental and Applied Mechanics, the first volume of eight from the Conference, brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Experimental Mechanics, including papers on: · General Dynamic Materials Response · Novel Dynamic Testing Techniques · Dynamic Fracture and Failure · Dynamic Behavior of Geo-materials · Dynamic Behavior of Composites and Multifunctional materials · Dynamic Behavior of Low-Impedance materials · Dynamic Modeling and Simulation of Dynamic Behavior of Materials · Quantitative Visualization of Dynamic Behavior of Materials · Shock/Blast Loading of Materials · Interface and Structural Dynamics · Material Response

Download or read book Modelling and Simulation of Sheet Metal Forming Processes written by Marta C. Oliveira and published by MDPI. This book was released on 2020-04-22 with total page 254 pages. Available in PDF, EPUB and Kindle. Book excerpt: The numerical simulation of sheet metal forming processes has become an indispensable tool for the design of components and their forming processes. This role was attained due to the huge impact in reducing time to market and the cost of developing new components in industries ranging from automotive to packing, as well as enabling an improved understanding of the deformation mechanisms and their interaction with process parameters. Despite being a consolidated tool, its potential for application continues to be discovered with the continuous need to simulate more complex processes, including the integration of the various processes involved in the production of a sheet metal component and the analysis of in-service behavior. The quest for more robust and sustainable processes has also changed its deterministic character into stochastic to be able to consider the scatter in mechanical properties induced by previous manufacturing processes. Faced with these challenges, this Special Issue presents scientific advances in the development of numerical tools that improve the prediction results for conventional forming process, enable the development of new forming processes, or contribute to the integration of several manufacturing processes, highlighting the growing multidisciplinary characteristic of this field.

Download or read book Advanced Applications in Manufacturing Engineering written by Mangey Ram and published by Woodhead Publishing. This book was released on 2018-10-29 with total page 278 pages. Available in PDF, EPUB and Kindle. Book excerpt: Advanced Applications in Manufacturing Engineering presents the latest research and development in manufacturing engineering across a range of areas, treating manufacturing engineering on an international and transnational scale. It considers various tools, techniques, strategies and methods in manufacturing engineering applications. With the latest knowledge in technology for engineering design and manufacture, this book provides systematic and comprehensive coverage on a topic that is a key driver in rapid economic development, and that can lead to economic benefits and improvements to quality of life on a large-scale. Presents the latest research and developments in manufacturing engineering Covers a comprehensive spread of manufacturing engineering areas for different tasks Discusses tools, techniques, strategies and methods in manufacturing engineering applications Considers manufacturing engineering at an international and transnational scale Enables the reader to learn advanced applications in manufacturing engineering

Download or read book Engineering Plasticity written by Z. R. Wang and published by John Wiley & Sons. This book was released on 2018-03-02 with total page 517 pages. Available in PDF, EPUB and Kindle. Book excerpt: An all-in-one guide to the theory and applications of plasticity in metal forming, featuring examples from the automobile and aerospace industries Provides a solid grounding in plasticity fundamentals and material properties Features models, theorems and analysis of processes and relationships related to plasticity, supported by extensive experimental data Offers a detailed discussion of recent advances and applications in metal forming

Download or read book Ductile Fracture After Complex Loading Histories written by Stephane Jean Marie Marcadet and published by . This book was released on 2015 with total page 173 pages. Available in PDF, EPUB and Kindle. Book excerpt: In engineering practice, sheet metal often fails after complex strain paths that deviate substantially from the widely studied proportional loading paths. Different from previous works on the ductile fracture of sheet metal, this thesis research addresses the experimental and modeling issues related to the crack initiation in advanced high strength steels after loading direction reversal. The main outcome of the present work is a fracture initiation model for proportional and non-proportional loading. The starting point of this thesis is a first chapter on the development of a micromechanically-motivated ductile fracture initiation model for metals for proportional loading. Its formulation is based on the assumption that the onset of fracture is imminent with the formation of a primary or secondary band of localization. Motivated by the results from a thorough unit cell analysis, it is assumed that fracture initiates after proportional loading if the linear combination of the Hosford equivalent stress and the normal stress acting on the plane of maximum shear reaches a critical value. A comprehensive fracture initiation model is then obtained after transforming the localization criterion from the stress space to the space of equivalent plastic strain, stress triaxiality and Lode angle parameter using the material's isotropic hardening law. Experimental results are presented for three different advanced high strength steels. For each material, the onset of fracture is characterized for five distinct stress states, including butterfly shear, notched tension, tension with a central hole, and punch experiments. The comparison of model predictions with the experimental results demonstrates that the proposed Hosford-Coulomb model can predict with satisfactory accuracy the instant of ductile fracture initiation in advanced high strength steels. In a subsequent chapter, experimental methods are developed to perform compression tension experiments. In addition, a finite strain constitutive model is proposed combining a Swift-Voce isotropic hardening law with two Frederick-Armstrong kinematic hardening rules and a Yoshida-Uemori type of hardening stagnation approach. The plasticity model parameters are identified from uniaxial tension-compression stress-strain curve measurements and finite element simulations of compression-tension experiments on notched specimens. The model predictions are validated through comparison with experimentally-measured load-displacement curves up to the onset of fracture, local surface strain measurements and longitudinal thickness profiles. The extracted loading paths to fracture show a significant increase in ductility as a function of the compressive pre-strain. The Hosford-Coulomb model is therefore integrated into a non-linear damage indicator modeling framework to provide a phenomenological description of the experimental results for monotonic and reverse loading. Another extension of the modeling framework is presented in a third chapter inspired by the results from loss of ellipticity analysis. It is demonstrated that the Hosford-Coulomb model can also be expressed in terms of a stress-state dependent critical hardening rate. Moreover, it is shown that the critical hardening rate approach provides accurate predictions of the instant of fracture initiation for both proportional and non-proportional loading conditions. Enhancements of the finite strain constitutive model are also proposed to enable a fast identification of all model parameters. The plasticity model parameters are identified from stress-strain curve measurements from shear loading reversal on specimens with a uniform thickness reduced gage section. The model is used to estimate the local strain and stress fields in fracture experiments after shear reversal. The extracted loading paths to fracture show a significant increase in ductility as a function of the strain at shear reversal, a feature that is readily predicted by the prosed critical hardening rate model.

Download or read book Simulation of Ductile Failure in Metals Under Dynamic Loading Conditions Using Advanced Material Damage Modeling written by and published by . This book was released on 2004 with total page 218 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report results from a contract tasking University of Cassino as follows: The contractor shall investigate the issue of advanced failure prediction and design by means of innovative material failure modeling and computational techniques. The specific tasks include: - the use and implementation of advanced material modeling incorporating damage. strain rate and temperature effects. in an extensive number of numerical simulations; - verification of the model effective predictive capabilities in a number of applications; - extension of the material model in order to incorporate advanced features needed in penetration mechanics simulations: - development of analytical tools to measure material response to high strain rates loadings using a simple instrumented Charpy pendulum.

Download or read book Metal Forming written by Chris V. Nielsen and published by Academic Press. This book was released on 2021-03-03 with total page 428 pages. Available in PDF, EPUB and Kindle. Book excerpt: Metal Forming: Formability, Simulation, and Tool Design focuses on metal formability, finite element modeling, and tool design, providing readers with an integrated overview of the theory, experimentation and practice of metal forming. The book includes formability and finite element topics, including insights on plastic instability, necking, nucleation and coalescence of voids. Chapters discuss the finite element method, including its accuracy, reliability and validity and finite element flow formulation, helping readers understand finite element formulations, iterative solution methods, friction and contact between objects, and other factors. The book's final sections discuss tool design for cold, warm and hot forming processes. Examples of tools, design guidelines, and information related to tool materials, lubricants, finishes, and tool failure are included as well. Provides fundamental, integrated knowledge on metal formability, finite element topics and tool design Outlines user perspectives on accuracy, reliability and validity of finite element modeling Discusses examples of tools, their design guidelines, tool lubricants, and tool failure Considers the role played by stress triaxiality and shear and introduces uncoupled ductile damage criteria Includes applications, worked examples and detailed techniques

Download or read book Numerical Prediction of Ductile Fracture Due to Moving Load written by Md Abdullah and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This study investigates the effect of moving load on ductile fracture of shipbuilding metals through numerical simulation. Quinton [1,2] and Alsos [3] investigated moving load's effect on metals, in the plastic regime, and found that moving load results in a significant reduction in plastic capacity of metals. This study complements their work by extending the scope of the work up to ductile fracture initiation which was accomplished by implementing state-of-art ductile fracture model in moving loading scenario. A state-of-art ductile fracture model has been implemented in this study by incorporating the knowledge acquired by research in the fracture mechanics arena. A stress state based fracture locus with strain rate and temperature effects has been selected as the ductile fracture criteria accordingly. Finite Element Method with Explicit Time Integration scheme deemed appropriate for numerical simulation and LS-DYNA has been chosen to accomplish this consequently. This study attempts to mitigate two significant limitations of maritime structural assessment techniques associated with ship-ice interaction; undue simplification of load definition and over conservatism on fracture strain selection. Ship-ice interaction is considered as stationary loading scenario while it should be categorised as moving loading condition in accidental overloading situations. In addition, these techniques also regard fracture strain to be constant and independent of stress state, whereas studies show that ductile fracture initiation is highly dependent on the stress state. This study provides a method to incorporate stress-state dependent state-of-art ductile fracture model for numerical investigation of moving load.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1995 with total page 702 pages. Available in PDF, EPUB and Kindle. Book excerpt: