應用微量流動電解液於電化學線放電加工石英玻璃之研究

Study of Wire Electrochemical Discharge Machining (WECDM) of Quartz Glass with Titrated Electrolyte Flow

郭寬淵(Kuan-yuan Kuo)

指導教授 ： 顏炳華

國立中央大學/工學院/機械工程學系/博士(2015年)

摘要

石英具有優異性質，但其硬脆特性，傳統加工方式很難在效率與精度二者兼顧，電化學放電加工是以高溫熔融並且蝕刻輔助加工，相當適合於石英材料，WECDM加工系統內絕緣氣膜結構控制不易及加工區域內電解液循環困難，因此，探討WECDM加工機制，開發新加工方式及改善微溝槽表面品質為本論文研究主題。
首先探討流動電解液對加工石英玻璃影響，及氣膜成形特性進行研究，實驗中以石墨粉末之導電特性，分散電化學放電之能量，提升加工後工件表面之精度。並進一步利用碳化矽粉之複合加工方式改善加工效率及精度。實驗結果顯示液滴法電化學放電線切割加工石英玻璃有良好效果，擴槽量及比直性均佳，但表面品質及精度卻無法有效控制。於電解液中加入石墨粉末或加入碳化矽，藉以達到控制精度及改善表面粗度。實驗結果顯示，在相同條件下未加入任何粉末之電解液WECDM加工其表面粗度值Ra＝1.13μm，在加入0.4wt％石墨於電解液時，表面粗度可達到Ra＝0.36μm，改善率為68％；在加入碳化矽5wt％於電解時，表面粗度可達到Ra＝0.22μm，改善率為80％，且在最適當條件下電解液用量極少。證明利用石墨或碳化矽粉之特性在滴定電解液中局部化加工石英玻璃，可有效改善表面品質及減少環境汙染、降低成本、達到1次加工減少加工工序等優點。

關鍵字

WECDM ； 微溝槽 ； 石英玻璃 ； 滴定電解液 ； 表面粗糙度

並列摘要

Quartz has excellent properties, but its brittleness property results in the difficulty of balance between efficiency and precision for traditional machining method. ECDM aids in machining with high temperature fusion and etching, and is very appropriate for quartz material. In WECDM machining system, uneasy control of insulation gas film structure and difficult electrolyte circulation in machining zone. Therefore, thesis topic is to explore WECDM machining mechanisms, development new methods and improve the micro slit surface quality.
First, investigate the flow of electrolyte influence on the processing of quartz glass, adding graphite powder or silicon carbide powder of composite processing methods to improve the processing efficiency and accuracy. From experimental results, the surface roughness value for electrolyte WECDM machining without adding any powder under the same condition is Ra＝1.13μm, while the surface roughness may achieve Ra＝0.36μm as 0.4wt％ of graphite is added into electrolyte . The improvement rate is 68%. As 5wt％ of silicon carbide is added into electrolyte, the surface roughness can achieve Ra＝0.22μm, that is, the improvement rate is 80%. Furthermore, electrolyte is used very few under the best appropriate condition. It is proved that the utilization of graphite or silicon carbide characteristics for local machining of quartz glass in titration electrolyte is advantageous of improving surface quality effectively, reducing environmental pollution, lowering cost, and achieving one-time machining to reduce machining procedures.

並列關鍵字

WECDM ； Micro slit ； Quartz glass ； droplet titration ； Surface Roughness

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