本論文使用分子動力學(Molecular Dynamics, MD)模擬金/銀奈米線在高溫熔煉狀態下進行快速冷卻之晶體型態，並進行拉伸模擬實驗，以探討合金奈米線的結晶度對變形機制、強度、延性之影響。
模擬結果顯示，金/銀合金奈米線的冷卻速率愈快，結晶度愈低；相反地，冷卻速率愈慢，結晶度愈高。局部結晶從兩邊之固定邊界傳遞到奈米線中間區域。若在室溫下給予一段鬆弛時間可驅使材料結晶度提升至一定的限度。非結晶合金奈米線在拉伸過程中會因彈/塑變行為而發生動態結晶之現象，其塑變機制不再以晶界的滑移為主，而是伴隨晶粒內的差排滑動同時進行。金/銀合金奈米線的結晶度愈低，試件之延性較好，但強度卻比完美晶體低，而鬆弛後的合金奈米線其結晶度相對提高，延性較低，其塑性變形與破斷機制由非結晶區的結構所主導。合金成份比例差異愈大，材料呈現非均質性，導致延性較差。

This study analyzes solidification behaviors of gold/silver nanowires after melting at high temperatures then rapid cooling and additionally mechanical properties and deformation behaviors of alloy nanowires also investigated with simple tension test after rapid cooling by using molecular dynamics simulation.
Results show that gold / silver alloy nanowires cooled by higher cooling rate, it will be lower crystallization; Conversely, cooled by slower cooling rate, it will be higher crystallization. Crystallization region pass from rigid boundaries to nanowire center region. Amorphous alloy nanowires crystallization increase during elastic and plastic deformation behavior,and that plastic deformation mechanisms are no longer dominated by grain boundary sliding, but accompanied by intragranular dislocation slip at same time. Gold / silver alloy nanowires have great ductility under tensile loading by higher rapid cooling rate,and the ductility is dominated by non-crystalline area. The greater the difference in the percentage of alloy composition, alloy nanowires will be heterogeneity and have poor ductility.

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