由於石英具有的硬脆特性，若以傳統之加工方式很難實現高精度、高效率、高可靠性的加工，特別是在微型零組件的製造上。電化學放電加工(Electro-chemical Discharge Machining, ECDM)是以高溫熔融材料，並且藉此高溫可加速蝕刻速率的非傳統加工方法，相當適合作為加工石英之微製程技術。而由於電化學放電加工主要是藉由電化學反應在電極表面形成之氣膜而產生放電現象之材料移除方式，所以氣膜的結構及穩定性為影響加工效率及精度之關鍵因素。然而於加工過程中，氣膜受到放電高熱的衝擊及電解液循環程度的差異，將使得氣膜結構處在不規則且動態變化的狀態下，造成放電品質的不穩定影響加工效率與品質。因此本研究將首先探討不同電極型式對於加工性能之影響，而後為了提升加工性能，擬以可調變磁場(電磁鐵)來輔助加工改善，提供不同於既有方向之偏向力(勞倫茲力)，使氣泡受到此勞倫茲力的影響而脫離電極表面，維持氣膜的穩定性與改善電解液循環效能，進而改善加工效率及精度。實驗結果得知，將表面無任何幾合特徵的圓柱電極改為表面具有螺旋溝槽的鑽頭電極，其加工時間縮短了73.8%，可大幅度的提升加工效率。而後再增加可調變磁場的輔助，其加工時間有49.5%的改善幅度，同時對於加工時間的標準差也有91.8%的穩定性提升。最後利用可調變磁場產生的不對稱氣膜型態，進一步提升電解液循環的能力，因此使得加工時間得以再有24.4%的提升。Since quartz is a hard and brittle material, it is difficult to achieve high efficiency and high reliability using conventional methods, especially in the manufacturing of micro parts and components. Electrochemical discharge machining (ECDM) is an emerging non-traditional machining process that involves high-temperature melting assisted by accelerated chemical etching. During ECDM, gas film will be formed on the tool electrode surface due to electrochemical reaction and then result in discharge phenomenon. Therefore both the structure and stability of gas film have significant effect factors on the efficiency and precision of machining. During ECDM, the impact of high heat discharged and the differences in electrolyte cycle cause gas film to be irregular in structure and unstable in status. As a result, both the quality and efficiency of ECDM are undermined. Therefore, this study will first explore the effect of different electrode types for processing performance, and in order to improve the stability of gas film structure, this study attempt to use the tunable magnetic field (electromagnet) effect keeps bubbles move quickly form the tool electrode. both the stability of gas film structure and the efficiency of electrolyte cycle in micro holes are greatly enhanced.According to the experimental results, by changing the electrode shape, that machining time was reduced by 73.8%, can be substantially improved processing efficiency. Then increase the tunable magnetic field, that machining time was reduced by 49.5%, and the standard deviation of the processing time achieve 91.8%. Finally, tunable magnetic field generated by asymmetric gas film type, further enhance the capacity of the electrolyte cycle. Thus machining time was reduced by 24.4% again.
