University of Groningen
Self-adaptive and self-healing nanocomposite tribocoatings
Cao, Huatang
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Publication date:
2019
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Cao, H. (2019). Self-adaptive and self-healing nanocomposite tribocoatings. University of Groningen.
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Self-adaptive and Self-healing
Nanocomposite Tribocoatings
The research presented in this thesis was performed in the Advanced Production Engineering (APE) group of Engineering and Technology institute Groningen (ENTEG) and Materials Science Group of Zernike Institute for Advanced Materials at the University of Groningen, The Netherlands.
This research was carried out under financial support by Chinese Scholarship Council (CSC, No. 201406160102).
Print: Zalsman Groningen B.V. Cover design: Huatang Cao
ISBN: 978-94-034-1547-5 (printed version) ISBN: 978-94-034-1546-8 (electronic version)
Self-adaptive and Self-healing
Nanocomposite Tribocoatings
PhD thesis
to obtain the degree of PhD at the
University of Groningen
on the authority of the
Rector Magnificus prof. E. Sterken
and in accordance with
the decision by the College of Deans.
This thesis will be defended in public on
Monday 25 March 2019 at 11.00 hours
by
Huatang Cao
born on 20 June 1987
in Hunan, China
Supervisors
Prof. Y.T. Pei
Prof. J.T.M. De Hosson
Assessment Committee
Prof. A. Cavaleiro
Prof. J. Post
Prof. A. Vakis
Contents
Chapter 1 Introduction ... 1
1.1 Tribology ... 1
1.2 Solid lubrication ... 3
1.3 Self-adaption and self-healing funcationality ... 7
1.4 Outline of the thesis ... 10
Reference ... 12
Chapter 2 Synthesis, characterization and testing of WS2/a-C(H) tribocoatings ... 17
2.1 Physical vapor sputtering ... 18
2. 2 Coating deposition ... 20 2.3 Characterization techniques ... 22 2.3.1 Microstructure characterization ... 22 2.3.2 Chemical composition ... 29 2.3.3 Mechanical testing ... 33 Reference ... 36
Chapter 3 Effect of carbon concentation and argon flow rate on the microstructrue and tribological properties of magnetron sputtered WS2/a-C coatings ... 39
3.1 Introduction ... 40
3. 2. Experimental procedures ... 41
3.2.1 Preparation of the WS2/a-C coatings ... 41
3.2.2 Characterization of the WS2/a-C coatings ... 42
3. 3. Results and discussions ... 46
3.3.1 Basical charcterisitic of WS2 ... 47
3.3.2 Chemical and structural characterization ... 48
3.3.3 Mechanical and tribological properties ... 51
3.4 Conclusion ... 58
Reference ... 59
Chapter 4 On the S/W stoichiometry and triboperformance of WSxC(H) coatings deposited by magnetron sputtering ... 63
4.1 Introduction ... 64
4. 3. Results and discussions ... 65
4.3.1 Chemical composition and structural characterization ... 66
4.3.2 Mechanical properties ... 74
4.3.3 Tribological properties ... 76
4.4 Conclusion ... 81
Reference ... 81
Chapter 5 Instant WS2 platelets reorientation of self-adaptive WS2/a-C tribocoating ... 87
5.1 Introduction ... 88
5. 2. Experimental procedures ... 88
5. 3. Results and discussions ... 89
5.3.1 Microstructure characterization ... 89
5.3.2 Tribological properties ... 90
5.3.3 Self-adaptive mechanism ... 91
5.4 Conclusion ... 94
Reference ... 94
Chapter 6 On the self-healing peroformance of WS2/a-C tribocoatings ... 97
6.1 Introduction ... 98 6. 2 Experimental procedures ... 99 6. 3 Results ... 100 6.3.1 Microstructural characterization ... 100 6.3.2 Self-healing of damages ... 101 6.4 Discussions ... 112 6.5 Conclusion ... 120 Reference ... 120
Chapter 7 Summary and outlook ... ……….……125
7.1 Summary ... 125
7.1 Outlook ... 127
Samenvatting ... ……….……133
Appendix ...137
