The Numerical Simulation And Experimental Research On Material Removal Of Spark Erosion In Micro-EDM

In micro electrical discharge machining, material removal on discharge is very complex, so it’sdifficult to accurately predict the electrode loss to improve the machining accuracy. Because it isdifficult to detect and observe the microscopic physical process by experimental methods andinstruments, therefore, in this paper, it has been looked upon the influence of the law of electrodepolarity, electrode materials and discharge energy to the material removal of spark erosion, by usingnumerical simulation and test method.On the basis of micro electrical discharge process and heat transfer theory, the heat propagationmodel of electrodes has been primarily established. Then the temperature distribution of anode andcathode with single pulse discharge is simulated respectively by using ANSYS. Single pulse dischargeexperiment is carried out by the orthogonal test method, and the material removal of spark erosion iscalculated by measuring the discharge pit size. By comparing the simulation results and experimentalresults, this paper summarized the influence of law of the electrode polarity, electrode materials anddischarge energy to material removal. Following are the main work:1、In the same discharge energy, a numerical simulation of the discharge temperature field andthe experiments of carbon fiber and the commonly used metal wire electrode brass, which are thesame model of20μm×Φ6μm, are made. Their wire erosions are contrasted and verified the superiorityof carbon fiber as wire electrode of μWEDM.2、The two electrodes are changed and in the different discharge energy, two electrodes oftungsten, having a diameter of20μm, are used for the numerical simulation and the experimentalresearch. The influence of discharge energy to material removal is analysed.3、By calculating the material removal of spark erosion and comparing the simulation results andexperimental results, this paper summarized the influence of law of the electrode polarity, electrodematerials and discharge energy to material removal.This study has the feasibility and the practical significance and provides theoretcal guidance forselecting the polarity and the materials, setting the discharge parameters, designing the micro pulsepower and improving the process parameters of Micro-EDM.