界面活性劑改善玻璃微孔電化學放電成形精度的影響

Effects of the surfactant additive improves the shape accuracy of the Micro-hole of the glass

王家威(Jia-Wei Wang)

指導教授 ： 顏炳華

國立中央大學/工學院/機械工程學系/碩士(2006年)

摘要

摘要

電化學放電加工被運用來加工陶瓷材料，但大多的研究上皆採用直流電為能量的輸入型態，以致微孔的入口處會有嚴重的擴孔現象，材料甚至會因連續的放電火花而產生微裂痕。因此本文以變化電極幾何形狀搭配脈衝電壓為電化學放電加工時的能量輸入形態，並結合界面活性劑在硼矽玻璃上鑽微孔，探討加工後微孔的形狀精度、尺寸及加工時間。
實驗結果發現，將直徑200μm之圓柱電極改成扁平電極，入口擴孔量有20％的改善率；接著，在電解液中添加界面活性劑，在添加的最佳濃度20ppm狀況下，微孔擴孔量的改善率可提昇至28％，但在加工時間上並無明顯改善。
最後以扁平電極搭配脈衝電壓為電化學放電加工時的能量輸入形態，並結合添加界面活性劑於電解液中，入口的擴孔量相較於最初以圓柱電極採用DC直流電壓輸入所鑽的微孔，有非常明顯的改善，且微孔的表面型態也獲得良好的改善。當在脈衝供給時間比脈衝休止時間比為2ms：1ms時達到最好，擴孔量改善率達60％，且加工時間可由86.6秒降至55秒。

關鍵字

玻璃加工 ； 電化學放電加工

並列摘要

Abstract

Most of the research used the rectified DC voltage to machine the micro-hole on the Borosilicate Glass in ECDM process. One of the drawbacks is seriously inlet reaming. Extremely, the material will form micro-crack because of continuously discharge spark. This study investigate the shape accuracy and size of the micro-hole and the machining time with changing the electrode geometry, finding the best switch on and switch off time ratio, and adding surfactant into the dielectric.
The experimental results show that the reaming of the micro-hole decrease 20% by changing cylinder electrode into flat side wall electrode, 28% by adding the best surfactant concentration combined the flat side wall electrode.
Finally, the flat side wall electrode combine the pulse voltage and add surfactant into dielectric. The result shows the distinct improvement in the inlet reaming and the machine time

並列關鍵字

glass machining ； ECDM

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