電化學放電加工(ECDM)是加工非導電材料的新興加工技術，具有殘留熱應力低、加工精度高、加工速率快以及電極磨耗低等優點。因過去的文獻較少在探討加工機制對於加工結果的影響，故本文主要在探討電極尖端之氣膜半徑對於加工結果的影響，以及如何去控制電極尖端之氣膜半徑大小。
本文研究中使用直徑100m之碳化鎢刀具作為工具電極，電解液採用添加乙醇(Ethanol)之氫氧化鉀(KOH)溶液，利用電化學放電加工對石英玻璃進行鑽孔加工，再使用高速攝影機去拍攝加工過程中電極之氣膜成長情形，分別使用不同電壓、頻率以及有無添加磁場等參數，以研究及分析電極之氣膜厚度以及微孔加工的影響。
實驗結果顯示，電極尖端加工電壓在40V時有最大之氣膜半徑，從40V開始，隨著電壓增加，氣膜半徑隨之變小。改變頻率觀察氣膜成長情形而發現頻率與氣膜半徑成反比。添加磁場可以減小微孔之過切量、錐度並提高微孔之真圓度。

Electrochemical discharge machining (ECDM) is one of the novel technologies applied on machining non-conductive materials. ECDM has serveral advantages, such as low residual stress on the surface, high quality, high machining rate and low tool electrode wear.Since previous references discussed about little the effects of machining mechanism, on the machining result so this thesis emphasizes how to control the radius of gas film formed on the tip of electrode.
In this thesis Tungsten Carbide knife with diameter of 100m is used as the electrode, and KOH added Ethanol as electrolyte, to drill the quartz glass by electrochemical discharge machining. High speed camera is used to record the gas film under different supply voltages, frequencies, and magnetic field etc. The effects of gas film of thickness on the micro hole machining is analyzed.
Experimental results show that gas film on the tip of electrode has the biggest radius as the supplied voltage is 40V. By increasing the supplied voltage, the gas film’s radius becomes smaller. The applied frequency and gas film’s radius are inversely proportional. Adding a proper magnetic field can decrease the overcut, taper, and enhance the roundness of micro hole.

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