Huang Ruining, Yi Ying, Zhu Erlei, Xiong Xiaogang
School of Mechanical Engineering and Automation, Harbin Institute of Technology, Shenzhen 518000, China.
College of Science and Engineering, Hamad Bin Khalifa University, Education City 34110, Qatar.
Micromachines (Basel). 2020 Oct 14;11(10):935. doi: 10.3390/mi11100935.
Micro-electro-discharge machining (μEDM) plays a significant role in miniaturization. Complex electrode manufacturing and a high wear ratio are bottlenecks for μEDM and seriously restrict the manufacturing of microcomponents. To solve the electrode problems in traditional EDM, a µEDM method using liquid metal as the machining electrode was developed. Briefly, a liquid-metal tip was suspended at the end of a capillary nozzle and used as the discharge electrode for sparking the workpiece and removing workpiece material. During discharge, the liquid electrode was continuously supplied to the nozzle to eliminate the effects of liquid consumption on the erosion process. The forming process of a liquid-metal electrode tip and the influence of an applied external pressure and electric field on the electrode shape were theoretically analyzed. The effects of external pressure and electric field on the material removal rate (MRR), liquid-metal consumption rate (LMCR), and groove width were experimentally analyzed. Simulation results showed that the external pressure and electric field had a large influence on the electrode shape. Experimental results showed that the geometry and shape of the liquid-metal electrode could be controlled and constrained; furthermore, liquid consumption could be well compensated, which was very suitable for µEDM.
微电火花加工（μEDM）在小型化过程中发挥着重要作用。复杂的电极制造和高磨损率是μEDM的瓶颈，严重制约了微部件的制造。为了解决传统电火花加工中的电极问题，开发了一种以液态金属作为加工电极的μEDM方法。简要来说，一个液态金属尖端悬浮在毛细管喷嘴的末端，并用作放电电极，对工件进行放电并去除工件材料。在放电过程中，液态电极不断供应到喷嘴，以消除液体消耗对侵蚀过程的影响。从理论上分析了液态金属电极尖端的形成过程以及外加压力和电场对电极形状的影响。通过实验分析了外加压力和电场对材料去除率（MRR）、液态金属消耗率（LMCR）和槽宽的影响。模拟结果表明，外加压力和电场对电极形状有很大影响。实验结果表明，液态金属电极的几何形状和形态可以得到控制和约束；此外，液体消耗能够得到很好的补偿，这非常适用于μEDM。
