本論文利用分子動力學(Molecular Dynamics, MD)模擬銅-鎳-鋁-鐵-鈦五種金屬元素以不同配對方式，組成一元至三元合金金屬玻璃，進行高溫熔融後，以不同冷卻速率淬火至室溫，觀察其結晶度，探討合金組成元素數量與組成合金的元素晶體結構之種類對金屬玻璃形成能力之影響；並以銅-鎳-鋁金屬玻璃作為基礎模型嵌入面心立方的銅-鎳-鋁合金圓球形晶種進行退火模擬，以孕核與成長動力學的冶金觀點探討不同溫度的臨界成核半徑，用以尋找金屬玻璃進行短時間退火後結晶度會下降的機理。
研究結果顯示，合金組成元素的數量與晶體結構的種類越多者，金屬玻璃形成能力越強。銅-鎳-鋁金屬玻璃中，當溫度高於玻璃轉換溫度後，晶核的臨界成核半徑較為明確，並且臨界成核半徑隨著溫度上升而增大，因此溫度越高，退火後系統中存在的有效晶粒越少。當退火溫度低於玻璃轉換溫度時無法有效消除晶核，金屬玻璃的結晶度無法下降，反而會因較大的晶核緩慢成長，使其結晶度上升；當退火溫度高於玻璃轉換溫度時可以消除部分小於臨界成核半徑之晶核，使金屬玻璃的結晶度下降，並在退火模擬一段時間後達到最低結晶度，隨後，若殘留的有效晶粒開始成長，將導致材料的結晶度再次上升。

This thesis studied the glass forming ability of Cu, Cu-Ni, Cu-Al, Cu-Ni-Al, Cu-Ni-Fe, Cu-Ni-Ti and Cu-Ti-Fe alloy systems by Molecular Dynamics (MD) simulation. The crystallinity of these alloys after quenching at different cooling rates was characterized to identify the effect of processes parameters and crystal structures of the elements in the alloy on the glass forming ability of the alloys. The result shows that the greater number of components and types of crystal structure of component elements, the stronger glass-forming ability of alloys is.
The mechanism of annealing-induced amorphization phenomenon was also investigated by a method. That embed spherical nucleuses of Cu-Ni-Al alloy with FCC structure in Cu-Ni-Al amorphous alloy system, and then annealed the system in different temperatures. Monitoring the annihilation or growth behavior of the nucleuses with different sizes identify the critical radius for nucleation (r_c) at different annealing temperature. The results showed that the effect of critical radius for nucleation of Cu-Ni-Al amorphous alloy was obvious when the annealing temperature above glass-transition temperature and enlarged the critical radius size when the temperature raised. That indicated more nucleus was annihilated during high temperature annealing process. When the annealing temperature was higher than the glass transition temperature, part of the crystal nuclei smaller than the critical radius could be eliminated, so that the crystallinity of the metallic glass was reduced, and the minimum crystallinity was reached after a period of annealing simulation. Then, if the residual effective crystal grains start growth would cause the crystallinity of the amorphous metal to rise again.

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