Mechanical Properties and Applications of Additively Manufactured
Thermoplastic Polyurethane Material
A thesis submitted in fulfilment of the requirements for the degree of Master of Engineering
Tao Xu
Bachelor of Engineering, Tongji University
School of Engineering
College of Science, Technology, Engineering and Maths
RMIT University
August 2021
Declaration
I certify that except where due acknowledgement has been made, the work is that of the
author alone; the work has not been submitted previously, in whole or in part, to qualify
for any other academic award; the content of the thesis is the result of work which has been
carried out since the official commencement date of the approved research program; any
editorial work, paid or unpaid, carried out by a third party is acknowledged; and, ethics
procedures and guidelines have been followed.
Tao Xu
23 August 2021
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Acknowledgements
First of all, I would like to give my heartfelt thanks to my senior supervisor, Professor
Yi Min (Mike) Xie, who provided me with the opportunity to study at RMIT and always
helped me with my research. It has been a great privilege and joy to study under his
guidance and supervision. I am particularly impressed by his sharp mind for detecting
extremely detailed problems that exist in my research, which profoundly inspires me to be
a rigorous and responsible researcher. Professor Xie is not only my academic leader but
also my life mentor. I am sure that I will forever benefit from his direction and treasure it
all of my life.
My sincere and hearty thanks and appreciation also go to my associate supervisor, Dr
Xiaoshan (Susanna) Lin. After every day’s busy and exhausting work, she still devoted her
considerate care and immense vigour in the supervision of my thesis writing, including the
suggestions on wording, the help in forming the structure, and the efforts to the refinement
of ideas in my thesis. Without her keen insights and constant encouragement, the thesis
would not have been finished.
I would like to thank all my current and former colleagues. I miss lunchtime with
Yulin Xiong, Hu Xu, Wei Li, Anbang Chen, Wenzheng Xu, Yunzhen he, Qi Cai, Zicheng
Zhuang, Minghao Bi and Zhonggao Chen. I wish to particularly thank Mr Dingwen Bao
for giving me considerable care during my life in Melbourne.
I am grateful for the support and company from my friends Zhouhan Jia, Hange Yang,
Shangchi Yao, Rong Peng, Chenxing Zuo, Qi Lu, Jiajun Fan, Bo Fan, Mengge Cai, Zhi Li,
Yilun Chen, Jiezhuoma La, Xinrong Jiang, and Xiaohan Sun. I would like to express my
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appreciation to my former teacher Mr Ercüment Görgül, who introduced me to Professor
Xie personally and offered me a lot of help and advice in my career.
I am thankful to Nanjing Ameba Engineering Structure Optimization Research Insti-
tute for providing technical support. I thank Mr Wei Shen for arranging the workspace
and experimental equipment and Mr Donghui Wang for helping me operate machines and
conduct manufacturing.
I thank my beloved girlfriend Yingqi Li, who has been with me and brought me count-
less laughs and happiness. We met in spring, however, when I saw her, a poem by Shake-
speare appeared in my mind: "Shall I compare thee to a summer’s day?"
I would like to express my appreciation for the funding for my research from the Aus-
tralian Research Council (grant number: FL190100014).
Finally, but most importantly, I would like to thank my parents, who offer me uncondi-
tional support and encourage me to pursue my dreams. I will keep your love in the quietest
place in my heart.
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Contents
1 Introduction 1
1.1 Overview .................................. 1
1.1.1 Two Commonly Used Additive Manufacturing Technologies . . . 2
1.1.2 Additively Manufactured TPU Material .............. 5
1.2 Problem Statement ............................. 5
1.3 Objectives and Scope ............................ 7
1.4 Layout of Thesis .............................. 8
2 Literature Review 9
2.1 Chemical Properties of TPU ........................ 9
2.2 TPU Particles ................................ 11
2.3 Thermal Behaviour of TPU Material . . . . . . . . . . . . . . . . . . . . 12
2.4 Mechanical properties of TPU Material . . . . . . . . . . . . . . . . . . 13
3 Tensile Tests of TPU Dumb-Bell Specimens Printed with Various Parameters 16
3.1 Introduction ................................. 16
3.2 Materials and Testing Methods . . . . . . . . . . . . . . . . . . . . . . . 17
3.2.1 Test Specimens ........................... 17
3.2.2 Processing Parameters . . . . . . . . . . . . . . . . . . . . . . . 18
3.2.3 Tensile Test Setup ......................... 21
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