本文以分子動力學模擬多元合金從高溫熔融狀態急速冷卻至室溫之微結構與強度變化情形，所使用之勢能函數為緊束法(Tight-Binding Method)之半經驗勢能函數，並以Honeycutt-Anderson analysis與拉伸試驗之應力應變分析討論製程參數包括添加元素數量、種類與比例對結構與強度之影響，並探討易於生成非晶質(amorphous)合金之操作變因。由模擬結果可知添加原子尺寸差異越大，添加之比例越高皆有助於非晶質相的生成，所以當等莫耳比例添加Zr元素可得到大量非晶質結構的合金，但非晶質合金中BCC結構皆佔有一定的比例，使得非晶質相的比例最多只可達80％，此BCC結構是由介金屬化合物與Zr保持在高溫之BCC結構所造成。而在拉伸試驗中發現非晶質合金幾乎不受尺寸效應的影響，其奈米線強度相當於塊材，可知非晶質合金之強度將遠大於晶格結構之合金，且非晶質合金中的強度將與添加之元素種類有關。最後提出分子動力學模擬之改進方向與可能推論，可做為未來研究之方向。

The present study investigates the microstructure and strength of multi-element alloy by quenching from the liquid with the theory of molecular dynamics simulation. The applied potential parameter is the semi-empirical potential parameter of the tight-binding method. The fabrication parameter is analyzed by Honeycutt-Anderson analysis and the relation between the stress and strain of the tensile test, including the influences of the types and proportions of the added elements on the structure and strength of alloy. The factor which caused the good amorphous formation was also investigated in this study. More bigger variations between the added atoms are, more easier to obtain high proportion of amorphous structure. By adding same proportion of zirconium atoms, comparing with other added atoms, large number of amorphous structure will be obtained in the result. Nevertheless, due to that there was specified proportion of BCC structure in the alloy, amorphous structure can only reach the maximum proportion of 80%. The BCC structure mostly composed of the intermetallic compound and the crystalline structure of zirconium at high temperature. Because the size effect of amorphous alloy is slight, the strength of nanowire is equivalent to its bulk material. This showed that the strength of amorphous alloy is far greater than that of crystalline alloy and the strength of amorphous alloy is with respect to the type of added atoms. Improvement and inference of molecular dynamics simulation were mentioned at the final of this study, which provided the aspect of future investigation.

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