本文主要探討摩擦力及暫態負載對銑削穩定性的影響。首先利用剪犁效應模式描述刀尖切削力，將犁切力展開獲得穩態犁切力、方向效應動態製程阻尼力、干涉效應動態製程阻尼力及其高階項。透過數值模擬觀察不同犁切阻尼力對加工穩定性之影響。方向與干涉效應之製程阻尼力兩者在數學形式相似且對穩定性影響能力相同。以半離散法及切削時域數值模擬發現動態製程阻尼力考慮方向與干涉效應者相較於僅考慮干涉效應者，在低轉速區極限切深曲線提升較高，因此利用剪犁效應模式應共同考慮刀尖犁切係數與製程阻尼係數預測銑削穩定圖。
來自結構介面或刀具與工件間摩擦力造成的非線性現象對切削加工穩定性有相當大影響，適當利用其可提升加工穩定性、加工品質及材料移除率。論文設定摩擦力形式為庫倫阻尼力，推導出振動系統之等效黏滯阻尼與結構振動振幅成反比。利用數值模擬分析銑削加工負載變化對暫態振動振幅及等效阻尼之影響。憑藉降低暫態振幅提升摩擦阻尼可改善或使加工系統維持穩定。最後以極限切深實驗驗證穩定葉瓣圖所預測展現之摩擦阻尼效應特徵，並進行切削實驗驗證不同加工暫態條件對銑削穩定性的影響，重現數值模擬所預測之銑削顫振非線性現象。

This thesis investigates the effect of tool edge friction force and transient loading on milling stability. First, cutting force is described by Dual-mechanism Global Cutting Constants (DGCC). The ploughing force is developed to obtain the static ploughing force, the directional effect dynamic process damping force, the interference effect dynamic process damping force and its high-order terms. The effects of different ploughing damping forces on machining stability are observed by numerical simulation. Both the direction and the interference effect of the process damping force are similar in mathematical form and have the same influence on stability. Therefore, prediction of milling stability should consider both the edge ploughing coefficient and the process damping coefficient.
The nonlinear phenomenon caused by the friction between the structural interface or the tool and the workpiece has a considerable impact on machining stability. Proper application improves machining stability, processing quality and material removal rate. The thesis sets the friction force to the Coulomb damping force and deduces that the equivalent viscous damping is inversely proportional to the structural vibration amplitude. Numerical simulation is used to analyze the influence of milling load variation on transient vibration amplitude and equivalent damping. Improving the friction damping by reducing the transient amplitude enhances the stability. Verify experimentally the influence of different transient conditions on milling stability and present the nonlinear phenomenon of milling by numerical simulation.

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