此研究以研磨速度1500-3200 m/min、下壓力0.5-0.7 bar、最小潤滑劑量 (MQL) 噴射壓力2.5-5 bar及150號、320號及600號砂紙對鈦合金試片進行研磨。實驗過程中，配合邏輯控制系統對研磨溫度及下壓力進行即時監測。在研磨溫度超過40 ℃及下壓力超過實驗設定值之1.25倍時，噴射MQL (碳酸氫鈉與高壓空氣之混合流體)，以達到降溫及潤滑的效果。此研究建立了研磨粒在研磨時的切削力學模型，並分析鈦合金試片之材料移除率 (MRR)、表面完整性及研磨粒在各時間區間下之磨耗型態。最後，利用反應曲面法 (response surface method, RSM) 得到在特定權重下之多指標優化操作參數。結果顯示，以實驗值校正後之切削力學模型可以達到83.98%的精準度。研磨後鈦合金之材料硬度可以保存~395HV0.025並延長其材料使用壽命。除此之外，研磨速度3200 m/min比1500 m/min之MRR增加34.4% (32.8 mg/min)，此乃因為研磨速度提高而增加了試片與砂紙的研磨距離，因此提升了材料移除量；下壓力0.7 bar比0.5 bar的MRR增加了21.4% (29.8 mg/min)，其原因為下壓力增加造成試片與砂紙間摩擦力及接觸面積提高而使材料移除增加。MQL之噴射壓力為5 bar時的材料移除率較2.5 bar時提升了6.3% (28 mg/min)，推測其原因為最小潤滑劑量之噴射壓力大，於砂紙表面之清潔及降溫效果越好，使得材料移除率的提升。

This paper presents the mechanics of grinding titanium alloys (Ti-6Al-4V) in minimum quantity lubrication to the aspects of material removal, surface integrity, temperature and wear of coated abrasives following with confirmation in experimental works. In slumping of soda-lime glass with titanium mould, surface quality and integrity were greatly improved however surface finish on the titanium mould was still problematic due to its inherence low thermal conductivity. In this work, the developed analytical model suggested the influences of grit number, grinding speed, normal load pressure and MQL on the material removal rate and surface quality. When the developed model was calibrated with experimental results, the appreciable precision level of 83.98% was resulted. The maximum material removal (89 mg/min) was produced when 150 mesh grits, (0.7 bar) normal pressure, (5 bar) blasting pressure of MQL and grinding speed of (3200 m/min) were employed. The produced fine surface (~Ra 0.1 μm) demonstrates the evolution of the adhesion, plastic deformation following the fretting and sealing actions on the workpiece surface. Whilst MQL provided instant effects to the work’s hardening and thermal softening in grinding, the improvement of microhardness (~395HV0.025) prolonged the tool life and benefited the productivity.

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