本文使用分子動力學模擬金/銀合金塊材，利用不同的冷卻速率為參數條件，探討固化時材料微結構之變化，並以相同的冷卻條件搭配切削模擬實驗，探討切削後結晶度、切削力與剪切面上之剪切角ψ之變化。原子間採用嵌入原子式(Embedded Atom Method) 勢能、Tight-binding勢能與Morse勢能函數模型。
模擬的結果顯示，越快冷卻速率凝固後塊材內的結晶度越低；反之，越慢冷卻速率凝固後塊材內的結晶度越高。在室溫增加鬆弛時間未能有效的提高材料結晶度，若要得到高結晶度，應使用較慢的降溫速率，或是使用適當的晶種。切削時因刀具給予材料系統的機械功可以誘發結晶，使加工表面的結晶度提升。隨著材料的結晶度提高，切削力也隨即上升與reverse Hall-Petch effect相符。相較於單晶銀(001)晶面[1 ‾00]方向的切削加工，成分比例1:1金/銀合金塊材切削力較大，且會隨著結晶度提升而增加。因為單晶材料具有多個滑動性統，因此，切削時剪切角變動幅度較結晶材料大。

The research studies the nanometric cutting of Au50Ag50 alloy bulk with the diamond tool by molecular dynamics. Using different cooling rates as a parameter conditions to explore the curing material microstructure changes. And using the same cooling conditions with cutting simulation experiments to explore the degree of crystallinity after cutting and cutting force and the shear angle on the shear plane. The interactions between atoms in the workpiece are described by a embedded-atom method(EAM) and Tight-binding(TB) and Morse potential.
The simulation results shows that when the faster the cooling rate after solidification within the bulk lower crystallinity; contrary, the slower cooling rate after solidification within the bulk higher crystallinity. Increase the relaxation time at room temperature can not effectively improve the crystalline material, to obtain a high degree of crystallinity, the slower the cooling rate should be used, or the use of appropriate crystal seed. Cutting tool to give material systems due to mechanical work can induce crystallization, the machined surface to enhance the degree of crystallinity. With the increased degree of crystallinity of the material, the cutting force also went up with the reverse Hall-Petch effect consistent. Compared to the single crystal of silver (001) [1 ‾00] cutting direction, the component ratio of 1:1 gold / silver alloy bulk cutting force and will improve as the crystallinity increases. Because the single crystal material has a plurality of sliding systems, therefore, change the cutting angle of shear rate of more large crystalline material.

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