design and development of a layer-based additive manufacturing

421 Pages·2008·6.1 MB·English

by  Chris Williams

DESIGN AND DEVELOPMENT OF A LAYER-BASED ADDITIVE
MANUFACTURING PROCESS FOR THE REALIZATION OF
METAL PARTS OF DESIGNED MESOSTRUCTURE

A Dissertation
Presented to
The Academic Faculty

by

Christopher Bryant Williams

In Partial Fulfillment
of the Requirements for the Degree
Doctor of Philosophy in Mechanical Engineering

Georgia Institute of Technology
April 2008

Copyright © 2008 by Christopher Bryant Williams
DESIGN AND DEVELOPMENT OF A LAYER-BASED ADDITIVE
MANUFACTURING PROCESS FOR THE REALIZATION OF
METAL PARTS OF DESIGNED MESOSTRUCTURE

Approved by:

David Rosen, Co-Chair Hamid Garmestani
Associate Chair for Graduate Studies Professor,
Professor, Mechanical Engineering Materials Science and Engineering

Farrokh Mistree, Co-Chair David McDowell
Associate Chair for GT Savannah Distinguished Chair in Metals Processing
Professor, Mechanical Engineering Regents’ Professor,
Mechanical Engineering
Joe Cochran
Shreyes Melkote
Professor Emeritus,
Professor, Mechanical Engineering
Materials Science and Engineering

Date Approved:
December 3, 2007
I dedicate this dissertation to my grandparents, John & Lena Belcher and Ernest &
Bessie Williams, as well as to my parents, Charles & Linda Williams, all of whom taught
me to leave a legacy of service to others.
ACKNOWLEDGEMENTS

I consider myself extremely fortunate to have found the Systems Realization
Laboratory (SRL) at Georgia Tech. When people asked me what I wanted in an advisor
and/or graduate school experience, my answer was simple; I wanted to work in an
environment where students and professors got together for dinner. The specific research
topic wasn’t at the top of my priorities, having an advisor with a “big name” wasn’t a
concern; instead, I wanted to find a place where I felt at home. Lucky for me, the SRL
not only met this primary requirement, but it also fulfilled the other, more traditional,
selection criteria as well. The working environment of the SRL made such an impression
on me during my initial visit that I chose the lab before I chose an advisor with whom to
work.
Fortunately, the selection of an advisor within the SRL was not difficult, as I was
given the opportunity to work with both Dr. Farrokh Mistree and Dr. David Rosen who
both displayed characteristics that I was searching for in a mentor. As my co-advisors, I
must first acknowledge their efforts as a team – I would like to thank them for broadening
my engineering knowledge, for assisting me in surpassing my own expectations, for
stressing scholarship in all that I do, for taking a “risk” in hiring one additional student in
the fall of 2000, for showing me a proper balance between teaching and research as a
professor, and of course, for establishing the SRL and its environment.
I thank Farrokh Mistree for his constant encouragement, for sharing his wisdom and
insight, and for fueling my passion of becoming a professor. I hope I can provide my
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future students a warm home, a bright smile, a strong sense of scholarship, academic
insight, and maybe an occasional hug just as he provided for me over these past years.
I thank David Rosen for his research insight, his encouragement, for pushing me to
be a better engineer, for providing me with challenging and rewarding research questions,
for adapting to my work habits (read: procrastination), and for encouraging me to better
them. I hope that I can provide my future students with the strong sense of curiosity,
insight, professionalism, and scholarship that he has instilled in me.
I also acknowledge the other professors of the SRL, Janet K. Allen, Bert Bras, and
Chris Paredis, who all contributed to my growth despite not being an official advisor. Dr.
Jack Lackey is yet another professor of the Woodruff School that mentored me (through
providing me with a basic understanding of ceramics processing) during my career here.
I also acknowledge the guidance and insight provided to me by the reading
committee of this dissertation: Dr. Joe Cochran, Dr. Hamid Garmestani, Dr. David
McDowell, and Dr. Shreyes Melkote. Special thanks are offered to Dr. Cochran for
being a tertiary research advisor to me during the completion of this dissertation. His
limitless knowledge of ceramics, reduction, and material science was invaluable in the
development of the secondary hypothesis of this work. Despite being officially retired,
Dr. Cochran met with me on several occasions to discuss this topic of research; and more
often than not, to review the fundamentals of materials science. I am grateful that he
always did so with patience, understanding, and enthusiasm. There is no doubt that this
research could not have been completed without the donation of his time, intellect, and
lab resources.
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In the same vein, Michael Middlemas, Tammy McCoy, and Laura Cerully
(graduate students in the School of Materials Science and Engineering) were all
instrumental in the completion of this research. Their constant support and assistance in
the reduction and sintering of the green ceramic parts that I created were invaluable.
Special thanks is offered to Michael Middlemas for spending countless hours tutoring me
in operating various pieces of equipment related to the materials science discipline. His
generous donation of time, knowledge, and lab resources will not be forgotten. I thank
Dr. Jin Lee, a research scientist of the GT Lightweight Structures Group for guiding and
assisting me at the beginning of this research – his suggestion to abandon the
stereolithography working principle early in the research was invaluable.
I acknowledge Mike Stewart and Sterling Skinner of the Woodruff school for
assisting me in obtaining the three-dimensional printing machine. I acknowledge Dr.
Scott Johnston for training me on the 3DP machine and for assisting me with the creation
of the mini-build bins. I also acknowledge the generosity of Joe Pechin, President of
Aero-Instant Spray Drying Services, for donating the spray-dried material used in this
research.
I acknowledge all of the members of the SRL, both present and past, for providing
an environment in which I enjoyed working. Special thanks are offered to Dr. Carolyn
Seepersad for bringing the research topic of this dissertation to my attention and for being
yet another co-advisor. I thank Dr. Marco Fernandez, Dr. Benay Sager, Dr. Jitesh
Panchal, Dr. Greg Mocko, Dr. Ameya Limaye, Andrew Schnell, and Nathan Rolander for
their continuing encouragement and support. I acknowledge current lab members Jamal
Wilson, Stephanie Thompson, Nathan Young, and Greg Graf for lending their ears and
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advice during the final trying months of completing this research. Jamal Wilson is
further acknowledged for assisting in the completion of Appendix A.
A special acknowledgement is offered to Dr. Matthew Chamberlain and Dr. Scott
Duncan for their friendship and support during my stay at Georgia Tech. The friendship
and memories that we established are some of the most important and enjoyable parts of
my stay in Atlanta. My graduate school experience would not have been as meaningful
as it was without them.
I gratefully acknowledge the support of a G. W. Woodruff Presidential Fellowship
and NSF Grants DMI-0522382 and IGERT-0221600. The latter grant represents the
funding offered by the Georgia Tech TI:GER program which deserves special
recognition for providing sufficient financial support for initiating this research.
Finally, I must attempt to express the amount of gratitude that I have for the
constant support and encouragement of my entire family. Specifically I thank my mom,
Linda Williams, and dad, Dr. Charles Williams, for instilling in me the importance of
education at a young age, and for constantly encouraging me throughout these many
years at Georgia Tech. I thank my sister, Dr. Lunetta Williams, for her support and
friendship, and for leading the way towards a PhD and assistant professorship position –
yet another example of her bravely forging a path in life in which I can follow. I also
offer gratitude to Dr. Richard Brantley, Diana Brantley, Dr. Jessica Brantley, Dr. Thomas
Fulton, and Gabriel Fulton for providing an additional warm, supportive, and caring
family for me to be a part of. I am extremely fortunate to have such a wonderful family.
Of course, no amount of words can express the gratitude that I owe my wife, Justine
Brantley, for her constant love and support during the completion of my PhD degree.
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Justine stood beside me and comforted me during the trying times; she stood in front of
me to lead the way forward as she completed her Master’s degree; and at times, she was
forced to stand behind me in order to push me and cheer me towards completion. Most
of all, I thank her for not losing faith in me during these many years at Georgia Tech, and
for supporting my dream to become a professor. I am truly lucky to be partnered with her
in our journey through life together.
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TABLE OF CONTENTS

ACKNOWLEDGEMENTS iv

LIST OF TABLES xiv

LIST OF FIGURES xix

NOMENCLATURE xxv

SUMMARY xxx

CHAPTER 1 LOW-DENSITY CELLULAR MATERIALS 1
1.1 LOW-DENSITY CELLULAR MATERIALS 2
1.1.1 Cellular Material Applications 3
1.1.2 Classification of Cellular Materials 4
1.2 MANUFACTURING CELLULAR MATERIALS 7
1.2.1 Stochastic Cellular Materials 7
1.2.2 Ordered Cellular Materials 11
1.2.3 Critical Analysis of Cellular Material Manufacturing 13
1.3 PRIMARY RESEARCH QUESTION: MANUFACTURING 16
CELLULAR MATERIALS WITH DESIGNED
MESOSTRUCTURE
1.3.1 Parts of Designed Mesostructure 16
1.3.2 Applications of Parts of Designed Mesostructure 16
1.3.3 Manufacturing Materials with Designed Mesostructure 17
1.3.4 Primary Research Question 21
1.4 ORGANIZATION OF THIS DISSERTATION 22
1.4.1 Phase One: Design 22
1.4.2 Phase Two: Embodiment 24
1.4.3 Phase Three: Modeling & Evaluation 25
1.4.4 Dissertation Roadmap 26

CHAPTER 2 DESIGN: CLARIFICATION OF TASK 28
2.1 MANUFACTRUING MATERIALS OF DESIGNED 28
MESOSTRUCTURE: PRELIMINARY REQUIREMENTS
2.2 DIRECT METAL ADDITIVE MANUFACTURING 30
2.2.1 Classification of Direct Metal Additive Manufacturing 31
Processes
2.2.2 One-Dimensional Energy Patterning of Powder Bed 34
2.2.3 One-Dimensional Material Patterning 41
2.2.4 One-Dimensional Patterning of Energy and Material 42
2.2.5 Two-Dimensional Material Patterning 44
2.2.6 Two-Dimensional Patterning of Energy and Material 45
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2.27 Critical Analysis of Direct Metal Additive Manufacturing of 46
Cellular Materials
2.3 MANUFACTURING LINEAR CELLULAR ALLOYS: 53
REDUCTION OF METAL OXIDES VIA THERMAL CHEMICAL
PROCESSING
2.3.1 Manufacturing Linear Cellular Alloys 54
2.3.3 Critical Analysis of the Linear Cellular Alloy Manufacturing 55
Process
2.4 PRIMARY RESEARCH HYPOTHESIS 59
2.5 MANUFACTURING PARTS WITH DESIGNED 60
MESOSTRUCTURE VIA ADDITIVE MANUFACTURING AND
REDUCTION OF METAL OXIDES: A REQUIREMENTS LIST
2.5.1 Geometry 61
2.5.2 Material 63
2.5.3 Production 64
2.5.4 Quality Control 64
2.5.5 The Requirements List 65
2.6 DISSERTATION ROADMAP 67

CHAPTER 3 DESIGN: IDENTIFICATION OF DESIGN TASK AND 69
WORKING PRINCIPLES
3.1 IDENTIFYING THE DESIGN TASK 69
3.1.1 Abstraction of Requirements 70
3.1.2 Crux of the Design Problem 75
3.2 FUNCTION STRUCTURE CREATION 76
3.2.1 Identification of Primary Functions 76
3.2.2 Identification of Sub-Functions 77
3.2.3 Function Structure 79
3.3 GENERATING WORKING PRINCIPLES 80
3.3.1 Store Material 81
3.3.2 Pattern Material 88
3.3.3 Pattern Energy 92
3.3.4 Create Primitive 95
3.3.5 Provide New Material 100
3.3.6 Support Previously Deposited Material 102
3.4 MORPHOLOGICAL MATRIX 104
3.5 DISSERTATION ROADMAP 108

CHAPTER 4 DESIGN: GENERATION OF WORKING STRUCTURES 111
4.1 ONE-DIMENSIONAL ENERGY PATTERNING WORKING 112
STRUCTURES
4.1.1 Laser Sintering (LS) 112
4.1.2 Stereolithography (SL) 116
4.2 TWO-DIMENSIONAL ENERGY PATTERNING WORKING 121
STRUCTURES
4.2.1 Two-Dimensional Sintering (HSS) 121
x