本研究旨在結合分子動力學模擬與高解析度背向散射電子繞射技術(HR-EBSD)，探討單晶銀奈米薄膜在奈米壓痕下的變形行為，透過經典赫茲接觸定律與應力-應變曲線的轉換求出材料的楊氏模數及降伏應力。並且分析不同晶格方向、壓頭速度及溫度對材料楊氏模數、初塑性應力與變形行為的影響，也會透過可視化軟體觀察模型壓痕後的微結構變化以探討塑性變形所造成的影響，最後會結合模擬與實驗結果，深入了解差排滑移產生對於高解析度背向散射電子繞射技術(HR-EBSD)測量上的影響。
研究結果顯示，[0 0 1]方向的楊氏模數最低且初塑性應力最小；壓痕速度升高會提升楊氏模數與pop-in點負載，但加劇應力-應變曲線的震盪；溫度升高則降低楊氏模數與初塑性應力。而塑行變形的產生(如差排滑移和疊層缺陷)會對材料的應力-應變值造成不同的影響。也特別分析差排滑移對周圍原子的影響，可發現會在各方向上有約20Å的影響範圍並引發顯著的晶格旋轉，且分析的旋轉軸向量表明，差排滑移系統的晶格旋轉方向與壓痕過程密切相關。此外，利用HR-EBSD技術測量圖譜變形並與分子模擬數據進行比較，可發現在低旋轉角度測量中具有較高準確性，但在差排滑移產生後，會明顯在測量上出現誤差。透過結合模擬數據的比較，能更準確反映HR-EBSD對於局部區域旋轉與應變值的測量情況。

This study aims to combine molecular dynamics (MD) simulations with high-resolution electron backscatter diffraction (HR-EBSD) techniques to investigate the deformation behavior of single-crystal silver (Ag) thin films under nanoindentation. The effects of different crystallographic orientations, indentation velocities, and temperatures on the material's deformation behavior are analyzed. Microstructural changes after indentation are examined using visualization software to explore the impact of plastic deformation. Finally, the influence of dislocation slip on HR-EBSD measurements is further explored.
The results show that different conditions such as crystal orientation, indenter speed, and temperature significantly affect the material's Young's modulus, initial plastic depth, initial plastic strain, and initial plastic stress. Slip deformation leads to a sharp drop in stress, while stacking fault structures show stress oscillations. Analyzing the effect of dislocation slip on surrounding atoms reveals that significant lattice rotation occurs. Comparisons between HR-EBSD measurements and MD simulation data reveal significant measurement errors after dislocation slip occurs. By integrating simulation data, HR-EBSD measurements of local lattice rotation and strain values can be more accurately reflected.

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