Thermo-Mechanical Modeling of Additive Manufacturing


Book Description

Thermo-mechanical Modeling of Additive Manufacturing provides the background, methodology and description of modeling techniques to enable the reader to perform their own accurate and reliable simulations of any additive process. Part I provides an in depth introduction to the fundamentals of additive manufacturing modeling, a description of adaptive mesh strategies, a thorough description of thermal losses and a discussion of residual stress and distortion. Part II applies the engineering fundamentals to direct energy deposition processes including laser cladding, LENS builds, large electron beam parts and an exploration of residual stress and deformation mitigation strategies. Part III concerns the thermo-mechanical modeling of powder bed processes with a description of the heat input model, classical thermo-mechanical modeling, and part scale modeling. The book serves as an essential reference for engineers and technicians in both industry and academia, performing both research and full-scale production. Additive manufacturing processes are revolutionizing production throughout industry. These technologies enable the cost-effective manufacture of small lot parts, rapid repair of damaged components and construction of previously impossible-to-produce geometries. However, the large thermal gradients inherent in these processes incur large residual stresses and mechanical distortion, which can push the finished component out of engineering tolerance. Costly trial-and-error methods are commonly used for failure mitigation. Finite element modeling provides a compelling alternative, allowing for the prediction of residual stresses and distortion, and thus a tool to investigate methods of failure mitigation prior to building. - Provides understanding of important components in the finite element modeling of additive manufacturing processes necessary to obtain accurate results - Offers a deeper understanding of how the thermal gradients inherent in additive manufacturing induce distortion and residual stresses, and how to mitigate these undesirable phenomena - Includes a set of strategies for the modeler to improve computational efficiency when simulating various additive manufacturing processes - Serves as an essential reference for engineers and technicians in both industry and academia




Computational Welding Mechanics


Book Description

Computational Welding Mechanics (CWM) provides readers with a complete introduction to the principles and applications of computational welding including coverage of the methods engineers and designers are using in computational welding mechanics to predict distortion and residual stress in welded structures, thereby creating safer, more reliable and lower cost structures. Drawing upon years of practical experience and the study of computational welding mechanics the authors instruct the reader how to: - understand and interpret computer simulation and virtual welding techniques including an in depth analysis of heat flow during welding, microstructure evolution and distortion analysis and fracture of welded structures, - relate CWM to the processes of design, build, inspect, regulate, operate and maintain welded structures, - apply computational welding mechanics to industries such as ship building, natural gas and automobile manufacturing. Ideally suited for practicing engineers and engineering students, Computational Welding Mechanics is a must-have book for understanding welded structures and recent technological advances in welding, and it provides a unified summary of recent research results contributed by other researchers.







Additive Manufacturing with Metals


Book Description

This textbook and reference provides a comprehensive treatment of additive manufacturing (AM) for metals, including design and digital work flows, process science and reliability, metallic systems, quality assurance, and applications. The book is rooted in the fundamental science necessary to develop and understand AM technologies, as well as the application of engineering principles covering several disciplines to successfully exploit this important technology. As additive manufacturing of metals is the fastest growing subset of this transformative technology, with the potential to make the widest impact to industrial production, Metals Additive Manufacturing: Design, Processes, Materials, Quality Assurance, and Applications is ideal for students in a range of engineering disciplines and practitioners working in aerospace, automotive, medical device manufacturing industries.




Predictive Theoretical and Computational Approaches for Additive Manufacturing


Book Description

Additive manufacturing (AM) methods have great potential for promoting transformative research in many fields across the vast spectrum of engineering and materials science. AM is one of the leading forms of advanced manufacturing which enables direct computer-aided design (CAD) to part production without part-specific tooling. In October 2015 the National Academies of Sciences, Engineering, and Medicine convened a workshop of experts from diverse communities to examine predictive theoretical and computational approaches for various AM technologies. While experimental workshops in AM have been held in the past, this workshop uniquely focused on theoretical and computational approaches and involved areas such as simulation-based engineering and science, integrated computational materials engineering, mechanics, materials science, manufacturing processes, and other specialized areas. This publication summarizes the presentations and discussions from the workshop.




Residual Stress Distributions in Additively Manufactured Parts


Book Description

Additive manufacturing (AM) of parts using a layer by layer approach has seen a rapid increase in application for production of net shape or near-net shape complex parts, especially in the field of aerospace, automotive, etc. Due to the superiority of manufacturing complex shapes with ease in comparison to the conventional methods, interest in these kinds of processes has increased. Among various methods in AM, laser powder bed fusion (LPBF) is one of the most widely used techniques to produce metallic components. As in all manufacturing processes, residual stress (RS) generation during manufacturing is a relevant issue for the AM process. RS in AM are generated due to a high thermal gradient between subsequent layers. The impact of residual stresses can be significant for the mechanical integrity of the built parts and understanding the generation of RS and the effect of AM process parameters is therefore important for a broader implementation of AM techniques. The work presented in this licentiate thesis aims to investigate the influence of build orientation on the RS distribution in AM parts. For this purpose, L-shaped Inconel 718 parts were printed by LPBF in three different orientations, 0°, 45°, and 90°, respectively. Inconel 718 was selected because it is a superalloy widely used for making gas turbine components. In addition, IN718 has in general good weldability which renders it a good material for additive manufacturing. Residual stress distributions in the parts removed from the build plate were measured using neutron diffraction technique. A simple finite element model was developed to predict the residual stresses and the effect of RS relaxation due to the separation of the parts and build plate. The trend of residual stress distribution predicted was in good agreement with experimental results. In general, compressive RS at the part center and tensile RS near the surface were found. However, while the part printed in 0° orientation had the least amount of RS in all three principal directions of part, the part built in 90° orientation possessed the highest amount of RS in both compression and tension. The study has shown that residual stress distributions in the parts are strongly dependent on the building process. Further, it has shown that the relaxation of RS associated with the removal of the parts from the build plate after printing has a great impact on the final distribution of residual stress in the parts. These results can be used as guidelines for choosing the orientations of the part during printing.




ASM Metals Reference Book, 3rd Edition


Book Description

This reference book makes it easy for anyone involved in materials selection, or in the design and manufacture of metallic structural components to quickly screen materials for a particular application. Information on practically all ferrous and nonferrous metals including powder metals is presented in tabular form for easy review and comparison between different materials. Included are chemical compositions, physical and mechanical properties, manufacturing processes, applications, pertinent specifications and standards, and test methods. Contents Overview: Glossary of metallurgical terms Selection of structural materials (specifications and standards, life cycle and failure modes, materials properties and design, and properties and applications) Physical data on the elements and alloys Testing and inspection Chemical composition and processing characteristics




Multiscale Modeling of Additively Manufactured Metals


Book Description

Multiscale Modeling of Additively Manufactured Metals: Application to Laser Powder Bed Fusion Process provides comprehensive coverage on the latest methodology in additive manufacturing (AM) modeling and simulation. Although there are extensive advances within the AM field, challenges to predictive theoretical and computational approaches still hinder the widespread adoption of AM. The book reviews metal additive materials and processes and discusses multiscale/multiphysics modeling strategies. In addition, coverage of modeling and simulation of AM process in order to understand the process-structure-property relationship is reviewed, along with the modeling of morphology evolution, phase transformation, and defect formation in AM parts. Residual stress, distortion, plasticity/damage in AM parts are also considered, with scales associated with the spatial, temporal and/or material domains reviewed. This book is useful for graduate students, engineers and professionals working on AM materials, equipment, process, development and modeling. - Includes the fundamental principles of additive manufacturing modeling techniques - Presents various modeling tools/software for AM modeling - Discusses various design methods and how to optimize the AM process using these models




Impact of Scientific Computing on Science and Society


Book Description

This book analyzes the impact of scientific computing in science and society over the coming decades. It presents advanced methods that can provide new possibilities to solve scientific problems and study important phenomena in society. The chapters cover Scientific computing as the third paradigm of science as well as the impact of scientific computing on natural sciences, environmental science, economics, social science, humanistic science, medicine, and engineering. Moreover, the book investigates scientific computing in high performance computing, quantum computing, and artificial intelligence environment and what it will be like in the 2030s and 2040s.




Heat Transfer in Polymer Composite Materials


Book Description

This book addresses general information, good practices and examples about thermo-physical properties, thermo-kinetic and thermo-mechanical couplings, instrumentation in thermal science, thermal optimization and infrared radiation.