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研究生：	曾彥鈞 Tseng, Yen-Chun
論文名稱：	含金屬玻璃之水化矽酸鈣的分子動力學研究 MOLECULAR DYNAMICS SIMULATION STUDY OF CSH CONTAINING METALLIC GLASS PARTICLES
指導教授：	王雲哲 Wang, Yun-Che
學位類別：	碩士 Master
系所名稱：	工學院 - 土木工程學系 Department of Civil Engineering
論文出版年：	2021
畢業學年度：	109
語文別：	英文
論文頁數：	86
中文關鍵詞：	分子動力學、水化矽酸鈣、金屬玻璃、石墨烯、複合材料、力學性質
外文關鍵詞：	Molecular dynamics simulation, CSH, Metallic glass, Graphene, Composite material, Mechanical properties
相關次數：	點閱：101 下載：0
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本篇論文對含有奈米尺度之金屬玻璃（MG）或石墨烯約束之金屬玻璃（GCMG）的水化矽酸鈣（CSH）進行了分子動力學（MD）模擬研究。包含石墨烯在內的用意是在於，可以在奈米尺度上構建特定幾何形狀的金屬玻璃，以避免由於表面能大於體能而使得金屬玻璃球形化。在本研究中，以Zr54Cu46 之原子數量比例選擇為代表性之金屬玻璃。我們在CSH 中嵌入了MG 或GCMG ，以期望獲得力學性能之增強，例如強度、延展性或阻尼。由於金屬玻璃和石墨烯具有優異的導電和導熱性能，因此這類型之複合材料的導電性和導熱性也可以提高。而由我們的MD模擬得到的結果顯示，由於 CSH 的層狀結構，該系統具有很強的各向異性。對於我們選擇的MG或GCMG之體積分率，MG-CSH 或GCMG-CSH 的楊氏模數與單軸壓縮下純CSH的楊氏模數大致相同。在受拉時，純CSH 表現出比MG-CSH 和GCMG-CSH 更大的楊氏模數和強度，這可能是因為較弱之界面誘導裂紋發生。在單軸正弦反覆加載下，MG-CSH 或GCMG-CSH 的整體機械阻尼比純CSH 大5 %。而內嵌金屬玻璃之CSH在熱傳導性質則具有高度方向性。由於金屬玻璃內嵌物的存在，垂直於層狀結構的有效 K33 可以提升不少。當存在金屬玻璃內嵌物時，其他兩個方向則有較低的熱傳導率。而由於石墨烯具有優異的導熱性質，GCMG-CSH 顯示出比MG-CSH 更好的導熱性質。在實際應用中，巨觀下具有螺旋幾何形狀的金屬玻璃纖維可以與CSH 提供更好的力學結合，因此可以提高整體強度和延展性。

Molecular dynamics (MD) simulation studies of calcium-silicate-hydrate (CSH) containing nanoscale metallic glass (MG) or graphene-confined metallic glass (GCMG) were conducted in this thesis research. Graphene confinement was to construct specific geometry of metallic glass at nanoscales to avoid spheronization due to surface energy greater than bulk energy. The Zr54Cu46 in atomic percentage was chosen as a representative metallic glass species in this study. We embedded the MG or GCMG inclusion in CSH to obtain possible enhancements in the mechanical properties, such as strength, ductility or damping. Electric and thermal conductivity may also be enhanced in such composites because of the excellent conductive properties in electricity and heat in metallic glass and graphene. Our MD simulations show that the system is strongly anisotropic due to the layered structure of CSH. With our chosen inclusion volume fraction, the Young’s modulus of MG-CSH or GCMG-CSH is about the same as that of pure CSH under uniaxial compression. When under tension, pure CSH exhibits larger Young’s modulus and strength than those of the MG-CSH and GCMG-CSH due to possibly weak interface induced crack initiation. Overall mechanical damping of MG-CSH or GCMG-CSH is 5%-larger than that of pure CSH under uniaxial sinusoidal loading. Effective thermal conductivity of the CSH containing metallic glass is strongly orientation dependent. Effective 33, perpendicular to the layers, can be largely enhanced due to the presence of the metallic glass inclusion. The other two directions show diminished thermal conductivity when the metallic glass inclusion is present. GCMG-CSH shows better thermal conductivity then MG-CSH due to graphene’s superior thermal conductivity. In real-world applications, macro-scale MG fibers with spiral geometry may provide better mechanical bonding with CSH, hence the overall strength and ductility can be enhanced.

CHINESE ABSTRACT i
ABSTRACT ii
ACKNOWLEDGMENTS iv
LIST OF TABLES vii
LIST OF FIGURES viii
NOMENCLATURE xiii
Introduction 1
1 Goals and motivation 1
2 Literature review 2
2.1 Amorphous solid - metallic glass 2
2.2 C-S-H research by MD 4
3 Outline of this thesis 7
Theoretical Backgrounds 8
1 Mechanical loss tangent 8
2 Molecular dynamics 9
3 Linear response theory 10
3.1 Classical linear response theory 10
4 Thermal conductivity 12
5 X-ray diffraction 14
6 Radial distribution function 15
Computational information 17
1 Atomistic models 19
1.1 C-S-H model 19
1.2 Metallic glasses 22
Results and discussion 24
1 Hybrid composite material MG/Graphene 24
1.1 Model building 25
1.2 Mechanical simulation about size effect of MG 28
1.2.1 Mechanical performance about size effect of MG 28
1.2.2 Effects of loading rates 32
1.2.3 Cubic MG model 37
1.2.4 Radial distribution function of MG 38
1.2.5 X-ray diffraction results 44
2 Mechanical properties of MG and hybrid MG/Graphene structure on C-S-H 46
2.1 C-S-H and MG and hybrid MG/Graphene composite model 46
2.2 Uniaxial loading tests on the CSH and composite model 48
2.3 Oscillatory loading 53
3 Thermal properties of MG and MG/Graphene structure on CSH 57
Conclusion and future work 58
1 Conclusion 58
2 Future work 60
LIST OF REFERENCES 61
APPENDICES
Appendix A: Presentation slides 63
VITA 85
Index 86
                                    

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校內：2026-08-27公開
校外：2026-08-27公開電子論文尚未授權公開，紙本請查館藏目錄

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