金屬玻璃由於其獨特的機械和物理性能而引起廣泛的關注，而奈米結構中又以奈米線特別受到注意，由於其優越的機械、光學和電學性質。本研究重點在於探討鎳-鋁金屬玻璃奈米線在奈米尺度下的機械以及材料性質。在模擬理論方法上，使用分子動力學法與EAM勢能函數作為理論基礎，並配合開放式軟體LAMMPS做為工具，分析在不同細長比、淬火速率、合金比例、壓縮速率、溫度、缺陷等條件下之鎳-鋁金屬玻璃奈米線受單軸壓縮情形，並且分析材料的應力分佈、晶相變化、剪應變、滑移系統以及金屬玻璃奈米線在壓縮下的挫曲情形。其結果顯示當淬火速率越低，極限應力和楊氏模數越高，而當在相同的淬火速率之下進行軸向壓縮，極限應力隨細長比的下降而上升。在合金比例的影響下，相具有最高的極限應力和楊氏模數。而當淬火速率在5K/ps和50K/ps時，奈米線對於溫度的影響無明顯的改變，不過當淬火速率下降到0.5K/ps時，奈米線的極限應力隨著溫度的上升而下降。當在較低的壓縮速率下，最大剪應變會發生在彎曲處，而當壓縮速率提升到0.5%/ps時，最大剪應變則會發生在固定端側，且有原子堆積的現象。而在金屬玻璃奈米線缺陷的影響中，淬火速率在0.5K/ps時，奈米線非晶比例受缺陷的影響最大，導致應力值下降的最多。

This study investigated the mechanical properties and deformation mechanism of Nix-Al100-x metallic glasses nanowires (NWs) at nanoscale. Molecular dynamics simulation was carried out using the program package LAMMPS with Embedded-Atom potential. Simulation was performed and focused on the effects of different slenderness ratio, quenching rate, alloy ratio, compression rate, temperature, defects and fracture process of Nix-Aly metallic glasses nanowires under uniaxial compression. Simulation results show that when the quenching rate is lower, the ultimate stress and the Young's modulus become higher. Moreover, under the same quenching rate, the ultimate stress increases with the decrease of the slenderness ratio. For different alloy ratio, it is found that  phase has the highest ultimate stress and Young's modulus. When the quenching rate is within the range from 5 to 50 K/ps, the effect of temperature is insignificant. However, when the quenching rate decreases to 0.5 K/ps, the ultimate stresses of nanowires decrease with the increase of temperature. Finally, the deformation mechanism and fracture phenomena are evaluated and discussed.

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