Download or read book Adaptive Multi level Model for Multi scale Ductile Fracture Analysis in Heterogeneous Aluminum Alloys written by Daniel Paquet and published by . This book was released on 2011 with total page 215 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Cast aluminum alloys and discontinuously reinforced aluminums (DRAs) are widely used in automotive, aerospace, nuclear and other engineering systems due to their advantageous strength-to-density ratio. Their microstructure is characterized by a dispersion of hard and brittle heterogeneities in a softer aluminum matrix. These microstructural heterogeneities increase the strength of the alloys, but also affect their failure properties like fracture toughness and ductility in an adverse manner. Important micromechanical damage modes that are responsible for deterring the overall failure properties include inclusion cracking, followed by ductile matrix failure due to void initiation, growth and coalescence. The complex interaction between competing damage modes makes failure and ductility prediction for these materials quite challenging. Sensitivity studies performed in this work with the locally enhanced Voronoi cell finite element method (LE-VCFEM) show a strong influence of microstructure morphology on ductile failure of microstructural domains. Unfortunately, micromechanical analysis of microstructural regions at the scale of structural components are prohibitive due to the enormous number of heterogeneities in the underlying microstructure.

Download or read book Multiscale Modeling of Complex Materials written by Tomasz Sadowski and published by Springer. This book was released on 2014-10-14 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: The papers in this volume deal with materials science, theoretical mechanics and experimental and computational techniques at multiple scales, providing a sound base and a framework for many applications which are hitherto treated in a phenomenological sense. The basic principles are formulated of multiscale modeling strategies towards modern complex multiphase materials subjected to various types of mechanical, thermal loadings and environmental effects. The focus is on problems where mechanics is highly coupled with other concurrent physical phenomena. Attention is also focused on the historical origins of multiscale modeling and foundations of continuum mechanics currently adopted to model non-classical continua with substructure, for which internal length scales play a crucial role.

Download or read book Integrated Multiscale Characterization and Modeling of Ductile Fracture in Heterogeneous Aluminum Alloys written by Dakshina M. Valiveti and published by . This book was released on 2009 with total page 131 pages. Available in PDF, EPUB and Kindle. Book excerpt: The multiscale model developed in this work captures detailed microscopic crack initiation and propagation in a large domain with minimal computational expense. The effectiveness of this multiscale characterization-modeling framework is demonstrated by studying structure-property relation and simulating ductile fracture in cast Aluminum alloy A319.

Download or read book Structural Integrity and Durability of Advanced Composites written by Peter Beaumont and published by Woodhead Publishing. This book was released on 2015-05-19 with total page 873 pages. Available in PDF, EPUB and Kindle. Book excerpt: Structural Integrity and Durability of Advanced Composites: Innovative Modelling Methods and Intelligent Design presents scientific and technological research from leading composite materials scientists and engineers that showcase the fundamental issues and practical problems that affect the development and exploitation of large composite structures. As predicting precisely where cracks may develop in materials under stress is an age old mystery in the design and building of large-scale engineering structures, the burden of testing to provide "fracture safe design" is imperative. Readers will learn to transfer key ideas from research and development to both the design engineer and end-user of composite materials. This comprehensive text provides the information users need to understand deformation and fracture phenomena resulting from impact, fatigue, creep, and stress corrosion cracking and how these phenomena can affect reliability, life expectancy, and the durability of structures. - Presents scientific and technological research from leading composite materials scientists and engineers that showcase fundamental issues and practical problems - Provides the information users need to understand deformation and fracture phenomena resulting from impact, fatigue, creep, and stress corrosion cracking - Enables readers to transfer key ideas from research and development to both the design engineer and end-user of composite materials

Download or read book Computational Methods for Microstructure Property Relationships written by Somnath Ghosh and published by Springer Science & Business Media. This book was released on 2010-11-17 with total page 669 pages. Available in PDF, EPUB and Kindle. Book excerpt: Computational Methods for Microstructure-Property Relationships introduces state-of-the-art advances in computational modeling approaches for materials structure-property relations. Written with an approach that recognizes the necessity of the engineering computational mechanics framework, this volume provides balanced treatment of heterogeneous materials structures within the microstructural and component scales. Encompassing both computational mechanics and computational materials science disciplines, this volume offers an analysis of the current techniques and selected topics important to industry researchers, such as deformation, creep and fatigue of primarily metallic materials. Researchers, engineers and professionals involved with predicting performance and failure of materials will find Computational Methods for Microstructure-Property Relationships a valuable reference.

Download or read book Experimental Investigation and Multi scale Modeling of Strain Localization Shear Banding and Fracture in Precipitation Hardened Aluminum Alloys written by Waqas Muhammad and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Finite element (FE) simulations are widely used in automotive design processes to model the forming and crashworthiness behavior of structural materials. Comprehensive material characterization and the availability of suitable constitutive models are prerequisites for accurate modeling of these operations. Numerical modeling of formability and crashworthiness is complex as it involves large deformations, instability, ruptures, damage propagation, and fracture. The effectiveness of computer-aided engineering (CAE) based design and performance evaluations significantly depends on the ability of numerical models to predict the material work hardening behavior, flow localization and fracture. This thesis presents a combined experimental and numerical study to explore microstructure property relationships involving strain localization, shear banding and fracture in precipitation hardened aluminum alloys. More specifically, the AA6xxx series aluminum alloys are of key interest for automotive applications, requiring good formability, hemmability and crash energy absorption characteristics. The goal of this work is to enhance the existing experimental understanding and modeling capabilities with respect to strain localization, shear banding and fracture in AA6xxx series precipitation hardened aluminum alloys, through development and coupling of multiscale modeling frameworks with advanced constitutive models for material work hardening and failure. In these regards, a crystal plasticity based constitutive hardening model is developed to account for the intragranular backstresses that arise from the formation of deformation induced dislocation substructure in precipitation hardened aluminum alloys. Based on thorough experimental investigation, it is learned that the substructure starts as pinned dislocation tangles with some regions having relatively high dislocation content while others being virtually dislocation free. With persistent deformation the substructure evolves into a well defined equiaxed cell/subgrain structure with majority of dislocations being trapped at the subgrain cell wall boundaries. The substructure induces intragranular backstresses due to blockage of dislocation passage leading to the experimentally observed Bauschinger effect at the macroscopic scale. The proposed hardening model accounts for these induced stresses and successfully predicts the experimentally measured flow behavior during cyclic simple shear and cyclic TCT and CTC loadings of AA6063. More importantly, the new backstress hardening model successfully reproduces the experimentally observed Bauschinger effect upon loading reversal. It is further shown that the crystallographic texture evolves significantly during cyclic simple shear deformation and the model successfully predicts the experimentally observed texture evolution. The study reveals that for proper prediction of flow behavior and the experimentally observed Bauschinger effect in precipitation hardened aluminum alloys, a physically motivated model that can account for the induced internal stresses, must be employed to describe material hardening on a polycrystalline level. Next, a multiscale modeling approach is developed where a macro-scale component level simulation is performed using conventional phenomenological plasticity and the boundary conditions of the region of interest are extracted and applied to the crystal plasticity based finite element model to account for the relevant microstructural physics. The proposed approach is successfully validated by simulating wrap-bending deformation of AA6063 and by comparing the observed texture evolution, slip band formation within grains, through thickness strain localization and the development of surface roughness with corresponding experimental data. The proposed approach enhances existing modeling capabilities for better predictability of material response under complex loading paths. After developing the multiscale framework, a new constitutive approach is developed to predict failure by extending the existing nano-void theory of ductile failure to precipitation hardened aluminum alloys by accounting for the effects of precipitation induced dislocation substructure on point defect generation. A new evolution law for the effective obstacle strength associated with substructure evolution is incorporated into the formulation. The proposed failure criterion is successfully validated against experimental data and its versatility is demonstrated by coupling the failure criterion with stress-strain data generated through crystal plasticity simulations, to predict failure strain for arbitrary loading - stress triaxiality conditions. Next, a comprehensive experimental investigation is performed to study the relationship between microstructure, plastic deformation and fracture behavior of precipitation hardened aluminum alloy AA6016 during bending. It is shown that the bendability of AA6016 alloy is limited by the formation of severe surface undulations and surface cracking, which are associated with the heterogenous nature of slip concentrating into coarse slip bands and intense shear banding originating from surface low cusps in the form of mutually orthogonal transgranular bands. Micro-cracks originate from low cusp regions along the outer tensile surface and propagate along the intensely sheared planes within shear bands. Results show that grains with S texture component are prone to shear banding and failure during bending and the contrary is true for Cube oriented grains. It is observed that intergranular micro-void nucleation and crack propagation is favored in areas with high grain boundary misorientations and intense slip band impingements along boundaries, perhaps due to the reduction in local cohesive strength of such boundaries. Finally, the developed multiscale modeling approach in conjunction with the newly developed hardening and failure models for age-hardenable aluminum alloys are applied to predict the experimentally observed shear banding and fracture behavior of AA6016 during bending. The simulated results successfully predict the experimentally observed shear banding and the predominant transgranular fracture behavior. It is shown that the advancing crack tip alternates from a less critical localization condition to a more critical one, as it requires lesser energy for the creation of new fracture surfaces while still sustaining the imposed plastic deformation. It is observed that Copper, Brass and Cube texture components show good resistance to shear banding and are therefore characterized as high bendability components, whereas the contrary is true for the S texture component. Lastly, the coupled numerical framework, presented herein, provides an excellent tool for CAE, virtual material characterization and analysis of microstructure-property relationships.

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 Practical Aspects of Computational Chemistry written by Jerzy Leszczynski and published by Springer Science & Business Media. This book was released on 2009-10-03 with total page 468 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Practical Aspects of Computational Chemistry" presents contributions on a range of aspects of Computational Chemistry applied to a variety of research fields. The chapters focus on recent theoretical developments which have been used to investigate structures and properties of large systems with minimal computational resources. Studies include those in the gas phase, various solvents, various aspects of computational multiscale modeling, Monte Carlo simulations, chirality, the multiple minima problem for protein folding, the nature of binding in different species and dihydrogen bonds, carbon nanotubes and hydrogen storage, adsorption and decomposition of organophosphorus compounds, X-ray crystallography, proton transfer, structure-activity relationships, a description of the REACH programs of the European Union for chemical regulatory purposes, reactions of nucleic acid bases with endogenous and exogenous reactive oxygen species and different aspects of nucleic acid bases, base pairs and base tetrads.

Download or read book Inelastic Analysis of Structures written by Milan Jirasek and published by John Wiley & Sons. This book was released on 2001-12-21 with total page 770 pages. Available in PDF, EPUB and Kindle. Book excerpt: Hat ein Werkstoff seine Elastizitatsgrenze erreicht, so verhalt er sich inelastisch. Ingenieure und Designer mussen wissen, mit welchen Eigenschaften dann zu rechnen ist. Dieser Band vermittelt Ihnen den aktuellen Wissensstand auf dem Gebiet des plastischen Verhaltens und der plastischen Zug-Spannungs-Beziehungen. Behandelt werden in erster Linie Baustoffe, vor allem Stahl, aber auch Beton und Boden. Eine ausgewogene Mischung aus qualitativer Diskussion und mathematischer Theorie! (05/00)

Download or read book The Scaled Boundary Finite Element Method written by Chongmin Song and published by John Wiley & Sons. This book was released on 2018-06-19 with total page 775 pages. Available in PDF, EPUB and Kindle. Book excerpt: An informative look at the theory, computer implementation, and application of the scaled boundary finite element method This reliable resource, complete with MATLAB, is an easy-to-understand introduction to the fundamental principles of the scaled boundary finite element method. It establishes the theory of the scaled boundary finite element method systematically as a general numerical procedure, providing the reader with a sound knowledge to expand the applications of this method to a broader scope. The book also presents the applications of the scaled boundary finite element to illustrate its salient features and potentials. The Scaled Boundary Finite Element Method: Introduction to Theory and Implementation covers the static and dynamic stress analysis of solids in two and three dimensions. The relevant concepts, theory and modelling issues of the scaled boundary finite element method are discussed and the unique features of the method are highlighted. The applications in computational fracture mechanics are detailed with numerical examples. A unified mesh generation procedure based on quadtree/octree algorithm is described. It also presents examples of fully automatic stress analysis of geometric models in NURBS, STL and digital images. Written in lucid and easy to understand language by the co-inventor of the scaled boundary element method Provides MATLAB as an integral part of the book with the code cross-referenced in the text and the use of the code illustrated by examples Presents new developments in the scaled boundary finite element method with illustrative examples so that readers can appreciate the significant features and potentials of this novel method—especially in emerging technologies such as 3D printing, virtual reality, and digital image-based analysis The Scaled Boundary Finite Element Method: Introduction to Theory and Implementation is an ideal book for researchers, software developers, numerical analysts, and postgraduate students in many fields of engineering and science.

Download or read book Scientific and Technical Aerospace Reports written by and published by . This book was released on 1983 with total page 1368 pages. Available in PDF, EPUB and Kindle. Book excerpt:

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 Bioinspired Structures and Design written by Wole Soboyejo and published by Cambridge University Press. This book was released on 2020-09-17 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: Master simple to advanced biomaterials and structures with this essential text. Featuring topics ranging from bionanoengineered materials to bio-inspired structures for spacecraft and bio-inspired robots, and covering issues such as motility, sensing, control and morphology, this highly illustrated text walks the reader through key scientific and practical engineering principles, discussing properties, applications and design. Presenting case studies for the design of materials and structures at the nano, micro, meso and macro-scales, and written by some of the leading experts on the subject, this is the ideal introduction to this emerging field for students in engineering and science as well as researchers.

Download or read book Multi Scale Continuum Mechanics Modelling of Fibre Reinforced Polymer Composites written by Wim Van Paepegem and published by Woodhead Publishing. This book was released on 2020-11-25 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt: Multi-scale modelling of composites is a very relevant topic in composites science. This is illustrated by the numerous sessions in the recent European and International Conferences on Composite Materials, but also by the fast developments in multi-scale modelling software tools, developed by large industrial players such as Siemens (Virtual Material Characterization toolkit and MultiMechanics virtual testing software), MSC/e-Xstream (Digimat software), Simulia (micromechanics plug-in in Abaqus), HyperSizer (Multi-scale design of composites), Altair (Altair Multiscale Designer) This book is intended to be an ideal reference on the latest advances in multi-scale modelling of fibre-reinforced polymer composites, that is accessible for both (young) researchers and end users of modelling software. We target three main groups: This book aims at a complete introduction and overview of the state-of-the-art in multi-scale modelling of composites in three axes: • ranging from prediction of homogenized elastic properties to nonlinear material behaviour • ranging from geometrical models for random packing of unidirectional fibres over meso-scale geometries for textile composites to orientation tensors for short fibre composites • ranging from damage modelling of unidirectionally reinforced composites over textile composites to short fibre-reinforced composites The book covers the three most important scales in multi-scale modelling of composites: (i) micro-scale, (ii) meso-scale and (iii) macro-scale. The nano-scale and related atomistic and molecular modelling approaches are deliberately excluded, since the book wants to focus on continuum mechanics and there are already a lot of dedicated books about polymer nanocomposites. A strong focus is put on physics-based damage modelling, in the sense that the chapters devote attention to modelling the different damage mechanisms (matrix cracking, fibre/matrix debonding, delamination, fibre fracture,...) in such a way that the underlying physics of the initiation and growth of these damage modes is respected. The book also gives room to not only discuss the finite element based approaches for multi-scale modelling, but also much faster methods that are popular in industrial software, such as Mean Field Homogenization methods (based on Mori-Tanaka and Eshelby solutions) and variational methods (shear lag theory and more advanced theories). Since the book targets a wide audience, the focus is put on the most common numerical approaches that are used in multi-scale modelling. Very specialized numerical methods like peridynamics modelling, Material Point Method, eXtended Finite Element Method (XFEM), isogeometric analysis, SPH (Smoothed Particle Hydrodynamics),... are excluded. Outline of the book The book is divided in three large parts, well balanced with each a similar number of chapters:

Download or read book Computational Mesomechanics of Composites written by Leon L. Mishnaevsky, Jr and published by John Wiley & Sons. This book was released on 2007-08-20 with total page 294 pages. Available in PDF, EPUB and Kindle. Book excerpt: Mechanical properties of composite materials can be improved by tailoring their microstructures. Optimal microstructures of composites, which ensure desired properties of composite materials, can be determined in computational experiments. The subject of this book is the computational analysis of interrelations between mechanical properties (e.g., strength, damage resistance stiffness) and microstructures of composites. The methods of mesomechanics of composites are reviewed, and applied to the modelling of the mechanical behaviour of different groups of composites. Individual chapters are devoted to the computational analysis of the microstructure- mechanical properties relationships of particle reinforced composites, functionally graded and particle clusters reinforced composites, interpenetrating phase and unidirectional fiber reinforced composites, and machining tools materials.

Download or read book Applied Mechanics Reviews written by and published by . This book was released on 1992 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Software for Exascale Computing SPPEXA 2016 2019 written by Hans-Joachim Bungartz and published by Springer Nature. This book was released on 2020-07-30 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt: This open access book summarizes the research done and results obtained in the second funding phase of the Priority Program 1648 "Software for Exascale Computing" (SPPEXA) of the German Research Foundation (DFG) presented at the SPPEXA Symposium in Dresden during October 21-23, 2019. In that respect, it both represents a continuation of Vol. 113 in Springer’s series Lecture Notes in Computational Science and Engineering, the corresponding report of SPPEXA’s first funding phase, and provides an overview of SPPEXA’s contributions towards exascale computing in today's sumpercomputer technology. The individual chapters address one or more of the research directions (1) computational algorithms, (2) system software, (3) application software, (4) data management and exploration, (5) programming, and (6) software tools. The book has an interdisciplinary appeal: scholars from computational sub-fields in computer science, mathematics, physics, or engineering will find it of particular interest.