Thermo-Mechanical Modeling of Additive Manufacturing

Michael Gouge, Pan Michaleris

• Publisher: Butterworth-Heinemann
• Year: 2017
• ISBN:
  9780128118214
• Topic: Technik & Maschinenbau
• Subtopic: Werkstoffwissenschaft

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

Acknowledgments

Chapter 1

The editors would like to thank Christina Gifford and Anna Valutkevich for making this book possible.

Chapter 2

The authors would like to thank Pan Michaleris for developing and documenting the modeling work contained in this chapter.

Chapter 3

The material is based upon work supported by the Office of Naval Research through the Naval Sea Systems Command under Contract No. N00024-02-D-6604, Delivery order No. 0611. Jarred C. Heigel is supported by the National Science Foundation under Grant No. DGE1255832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. The authors would like to thank Pan Computing LLC for the generous use of their computing resources and access to the Netfabb Simulation FE code. The authors would also like to thank Guy Showers and Douglas E. Wolfe for providing the surface roughness measurements.

Chapter 4

The material is based upon work supported by the Office of Naval Research through the Naval Sea Systems Command under Contract No. N00024-02-D-6604, Delivery order No. 0611. The authors would like to thank Pan Computing LLC for the generous use of their computing resources and access to the Netfabb Simulation FE code.

Chapter 6

Yanzhou Ji and Long-Qing Chen acknowledge the financial support from the American Makes National Additive Manufacturing Innovation Institute (NAMII) under grant number FA8650-12-2-7230. Lei Chen is grateful for the financial support by the Start-up funding and the cross-college working group grant from Mississippi State University. The authors acknowledge Dr. Fan Zhang at CompuTherm LLC for providing the Ti-Al-V thermodynamic database; Dr. Alphonse A. Antonysamy at GKN Aerospace for providing the microstructure figures of additively manufactured Ti-6Al-4V. The authors are also grateful for Dr. Tae Wook Heo at Lawrence Livermore National Laboratory and Dr. Nan Wang at McGill University for useful discussions on model development.

Chapter 7

The authors gratefully acknowledge the financial support of America Makes - Multi-Sensor Thermal Imaging for Additive Manufacturing. This work is built upon early efforts under ONR SBIR. The authors would like to acknowledge ARL Penn State and Penn State University's Center for Innovative Material Processing through Direct Digital Deposition (CIMP-3D) for use of facilities and equipment. This material is based on research sponsored by Air Force Research Laboratory under agreement number FA8650-12-2-7230. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon. The views and conclusions contained herein are those of the authors and should not be interpreted as necessarily representing the official policies or endorsements.

Chapter 8

This work was partially completed under funding from NSF Grant No. DGE1255832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation.

Chapter 9

This work was sponsored by a subcontract from Sciaky Inc. and funded by AFRL SBIR #FA8650-11-C-5165. Jarred Heigel contributed into this work under funding from NSF Grant No. DGE1255832. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation. The authors would also like to acknowledge partial support of this research by the Open Manufacturing program of the Defense Advanced Research Projects Agency and the Office of Naval Research through Grant N00014-12-1-0840. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation, the Department of Defense or the U.S. Government. Distribution Statement A: Approved for Public Release, Distribution Unlimited.

Chapter 10

This work was sponsored by a subcontract from Sciaky Inc. and funded by AFRL SBIR #FA8650-11-C-5165.

Chapter 11

This work was sponsored by a subcontract from Sciaky Inc. and funded by AFRL SBIR #FA8650-11-C-5165. The authors would also like to acknowledge partial support of this research by the Open Manufacturing program of the Defense Advanced Research Projects Agency and the Office of Naval Research through Grant N00014-12-1-0840. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the National Science Foundation, the Department of Defense or the U.S. Government. Distribution Statement A: Approved for Public Release, Distribution Unlimited.

Chapter 12

The author would like to thank Pan Computing LLC and Autodesk Inc. for the use of the Netfabb Simulation FE software.

Chapter 13

The author would like to thank Pan Computing LLC and Autodesk Inc. for the use of the Netfabb Simulation FE software.

Chapter 14

Laboratory activities conducted during this research were conducted at the Center for Innovative Materials Processing through Direct Digital Deposition at Penn State. This material is based on research sponsored by Air Force Research Laboratory under agreement number FA8650-12-2-7230 and by the Commonwealth of Pennsylvania, acting through the Department of Community and Economic Development, under Contract Number C000053981. The U.S. Government is authorized to reproduce and distribute reprints for Governmental purposes notwithstanding any copyright notation thereon. Any opinions, views, findings, recommendations, and conclusions contained herein are those of the author(s) and should not be interpreted as necessarily representing the official policies or endorsements, either expressed or implied, of the Air Force Research Laboratory, the U.S. Government, the Commonwealth of Pennsylvania, Carnegie Mellon University, or Lehigh University. The authors would like to thank Schlumberger-Doll Research for their support of this effort. Any opinions, findings, conclusions, and/or recommendations in this chapter are those of the authors and do not necessarily reflect the views of Schlumberger-Doll Research or its employees.

Chapter 15

This chapter was completed using work developed by the America Makes project “Development of Distortion Prediction and Compensation Methods for Metal Powder-Bed AM (Project 4026.001).” The authors would like to thank GEGRC, UTRC, and Honeywell Aerospace for their work in this project. The authors would also like to thank Pan Computing LLC and Autodesk Inc. for the use of the Netfabb Simulation FE software.

Part I

The Fundamentals of Additive Manufacturing Modeling

Outline

Chapter 1. An Introduction to Additive Manufacturing Processes and Their Modeling Challenges

Chapter 2. The Finite Element Method for the Thermo-Mechanical Modeling of Additive Manufacturing Processes

Chapter 1

An Introduction to Additive Manufacturing Processes and Their Modeling Challenges

Michael Gouge; Pan Michaleris Product Development Group, Autodesk Inc., State College, PA, United States

Abstract

This chapter introduces the topic of additive manufacturing simulation. The motivation for modeling AM processes and mitigating build failure without costly iterative experiments is detailed. A short survey of modeling literature for welding, directed energy deposition, and powder bed fusion processes is made. A list of the primary challenges in the modeling additive processes is given, and each challenge is described in further detail, with references to how these challenges are overcome in the remainder of the book.

Keywords

Additive manufacturing; directed energy deposition; laser power bed fusion; boundary conditions; finite element model; additive welding; microstructure evolution; distortion; thermal conduction; thermal gradient; residual stress; coupled models; decoupled models; anisotropy; phase transformation

1.1 Motivation

Additive manufacturing (AM) is experiencing a resurgence. While the public interest and knowledge of additive or more colloquially, 3D printing processes is a recent phenomena, this technology has be in use for four decades. Mul...

Table of contents

• Cover image
• Title page
• Table of Contents
• Copyright
• List of Contributors
• About the Editors
• Acknowledgments
• Part I: The Fundamentals of Additive Manufacturing Modeling
• Chapter 1: An Introduction to Additive Manufacturing Processes and Their Modeling Challenges
• Chapter 2: The Finite Element Method for the Thermo-Mechanical Modeling of Additive Manufacturing Processes
• Part II: Thermomechanical Modeling of Direct Energy Deposition Processes
• Chapter 3: Convection Boundary Losses During Laser Cladding
• Chapter 4: Conduction Losses due to Part Fixturing During Laser Cladding
• Chapter 5: Microstructure and Mechanical Properties of AM Builds
• Chapter 6: Understanding Microstructure Evolution During Additive Manufacturing of Metallic Alloys Using Phase-Field Modeling
• Chapter 7: Modeling Microstructure of AM Processes Using the FE Method
• Chapter 8: Thermo-Mechanical Modeling of Thin Wall Builds using Powder Fed Directed Energy Deposition
• Chapter 9: Residual Stress and Distortion Modeling of Electron Beam Direct Manufacturing Ti-6Al-4V
• Chapter 10: Thermo-Mechanical Modeling of Large Electron Beam Builds
• Chapter 11: Mitigation of Distortion in Large Additive Manufacturing Parts
• Part III: Thermomechanical Modeling of Powder Bed Processes
• Chapter 12: Development and Numerical Verification of a Dynamic Adaptive Mesh Coarsening Strategy for Simulating Laser Power Bed Fusion Processes
• Chapter 13: Thermomechanical Model Development and In Situ Experimental Validation of the Laser Powder-Bed Fusion Process
• Chapter 14: Study of the Evolution of Distortion During the Powder Bed Fusion Build Process Using a Combined Experimental and Modeling Approach
• Chapter 15: Validation of the American Makes Builds
• Appendix A: Appendix
• Index