本研究為在介電液中添加石墨烯粉末並採單邊缺口電極對Inconel 718鎳基超合金進行微孔放電加工，使用線放電研削機構(WEDG)將加工電極修製為單邊缺口，針對Inconel 718材料試片進行微孔加工實驗，並於添加石墨烯粉末情形下，探討峰值電流、間隙電壓、脈衝時間和電極轉速等加工參數對加工時間、電極消耗率及微孔加工精度之影響，實驗後利用掃描式電子顯微鏡和雷射共軛聚焦顯微鏡進行微孔內壁觀察，比較有、無添加石墨烯粉末微孔放電加工之實驗結果差異。
實驗研究結果顯示，採單邊缺口電極並在介電液中添加石墨烯粉末後對Inconel 718鎳基超合金進行微孔放電加工，可由旋轉之缺口電極促進介電液循環及排渣效果，並藉由添加石墨烯粉末達到分散放電的效果，相較於未添加石墨烯粉末的實驗結果，當採用間隙電壓50 V、峰值電流2 A、脈衝時間10 μs、衝擊係數40%、電極轉速1150 rpm加工參數組合時，於添加石墨烯粉末微孔放電加工情形下，加工時間降低了3.7%、入口擴孔率降低了3.1%和出口擴孔率降低了8.2 %，且表面粗糙度平均值降低了38.84%。

This study presents an experiment in micro-hole electric discharge machining (EDM) on Inconel 718 by adding graphene powder in the dielectric fluid. Unilateral notched electrode was used to perform the experiment. After the unilateral notched electrode was fabricated by WEDG process, micro-hole EDM was performed on the Inconel 718 work-piece. The effect of peak current, gap voltage, duration time and rotational speed on working time, electrode tool wear and machining quality were discussed in the experiment. Scanning Electron Microscope (SEM) and Laser Confocal Scanning Microscope (LSCM) were also utilized to observe the sidewall of the micro-hole. The results of micro-hole EDM with and without graphene powder adding were compared after the experiment.
The experimental results show that the application of the rotating unilateral notched electrode can promote dielectric fluid circulation and discharge the debris in micro-hole EDM on Inconel 718 nickel based superalloy. Disperse discharge can be achieved by adding graphene powder. Compared to micro-hole EDM without graphene powder, when the gap voltage is 50 V, the peak current is 2 A, the duration time is 10 s, the impact factor is 40 %, and the ratation speed is 1150 rpm, in the case of the EDM with graphene powder reveals that the processing time was reduced 3.7 %, the inlet reaming rate was reduced 3.1 %, the outlet reaming rate was reduced 8.2 %, and the average surface roughness was reduced 38.84 %.

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