| Mirror-Finish EDM is wildly used in precision molds and precision components machining. Powder-mixed EDM became an effective method to achieve mirror surface since last century, and made great progress thereafter. In powder-mixed EDM, the existence of powder particles affects the physical and chemical nature of the working fluid and improves the discharge condition. Powder particles increase the discharge gap and improve the discharge stability. However, powder-mixed EDM technology has some limitations. For example, the deposition of solid powder affected the processing stability. In addition, to prevent the powder deposition, certain circular, filter and stirrer system should be adopted, which increased the production costs. Besides, the solid powder would harm the worker. Thus, it is necessary to find new kind of addictive that can suspend in the dielectric stably to replace powers such as silicon and aluminum.Based on PMEDM, a new method that adds liquid microemulsion into the dielectric to achieve near-mirror surface is adopted in this thesis.The influence of Liquid Microemusion on discharge state was studied. Compared with EDM in ordinary kerosene based dielectric fluid, EDM in Liquid Microemusion added dielectric demonstrates larger effective discharge number in unit time, shorter ignition delay and lower spark maintaining voltage.The experimental study of the influences of machining parameters on surface quality in EDM in liquid Microemusion added dielectric was conducted. The proper machining condition and parameters to get a fine surface was achieved.Finally, the influence of Liquid Microemusion and common kerosene work fluid on the surface quality was studied. The experiments validated the effectiveness of Liquid Microemusion in achieving higher material removal rate, smoother surface roughness and less micro cracks.The study revealed that EDM in Liquid Microemusion added dielectric is potential in achieving mirror surface, and is worthy to be further studied.
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