Near dry electrical discharge machining
Near dry electrical discharge machining
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DOI：
10.1016/j.ijmachtools.2007.06.001
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发表时间：
2007-12
影响因子：
14
通讯作者：
C. Kao;J. Tao;A. Shih
中科院分区：
文献类型：
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作者：
C. Kao;J. Tao;A. Shih
本研究探讨近干式电火花加工制程。近干电火花加工使用液-气混合物作为两相电介质流体，并且具有调整液体浓度和电介质性质以满足期望性能目标的好处。最小量润滑（MQL）分配器用于以受控速率向工件和电极之间的差距提供微量液滴。研究了电火花线切割和电火花钻孔在湿、干和近干条件下的加工性能。水和空气的混合物是本研究中用于近干式电火花加工的介质液。与干式电火花加工相比，近干式电火花加工具有更高的材料去除率、更锋利的切削刃和更少的碎屑沉积等优点。与湿式电火花加工相比，近干式电火花加工在低放电能量下具有更高的材料去除率，并且产生更小的间隙距离。然而，近干EDM在电极上放置较高的热负荷，这导致线EDM中的线断裂，并且增加EDM钻孔中的电极磨损。假设差距距离由放电距离和材料去除深度组成，建立了一个数学模型，定量关联的水-空气混合物的介电强度和粘度的差距距离。
This study investigates the near dry electrical discharge machining (EDM) process. Near dry EDM uses liquid–gas mixture as the two phase dielectric fluid and has the benefit to tailor the concentration of liquid and properties of dielectric medium to meet desired performance targets. A dispenser for minimum quantity lubrication (MQL) is utilized to supply a minute amount of liquid droplets at a controlled rate to the gap between the workpiece and electrode. Wire EDM cutting and EDM drilling are investigated under the wet, dry, and near dry conditions. The mixture of water and air is the dielectric fluid used for near dry EDM in this study. Near dry EDM shows advantages over the dry EDM in higher material removal rate (MRR), sharper cutting edge, and less debris deposition. Compared to wet EDM, near dry EDM has higher material removal rate at low discharge energy and generates a smaller gap distance. However, near dry EDM places a higher thermal load on the electrode, which leads to wire breakage in wire EDM and increases electrode wear in EDM drilling. A mathematical model, assuming that the gap distance consists of the discharge distance and material removal depth, was developed to quantitatively correlate the water–air mixture's dielectric strength and viscosity to the gap distance.