- Jan 30, 2018-

         EDM is the use of immersion in the working fluid between the bipolar pulse discharge generated by the erosion of the conductive material to remove the special processing methods, also known as EDM or EDM, English referred to as EDM.

working principle           For EDM, the tool electrode and the workpiece are connected to the poles of the pulse power supply, and immersed in the working fluid, or the working fluid into the discharge gap. Through the gap automatic control system to control the tool electrode feed to the workpiece, when the gap between the two electrodes to reach a certain distance, the pulse voltage applied to the two electrodes breakdown of the working fluid, resulting in spark discharge. In the discharge of the fine channel instantaneous concentration of a large number of thermal energy, the temperature can be as high as 10,000 degrees Celsius, the pressure has also drastic changes, so that this part of the work surface local trace of the metal material immediately melting, gasification and explosive splash to the working fluid In the rapid condensation, the formation of solid metal particles, the working fluid away. At this time left in the workpiece surface will leave a small pit marks, discharge a brief pause, the working fluid between the two electrodes to restore insulation.

         Next, the next pulse voltage breaks down at another point where the two electrodes are relatively close to each other to generate a spark discharge, and the above process is repeated. In this way, although the amount of metal removed by each pulse discharge is very small, more metals can be removed due to thousands of pulse discharges per second, resulting in a certain productivity. The tool electrode is continuously fed to the workpiece while the workpiece metal is being etched while maintaining a constant discharge gap between the tool electrode and the workpiece, and finally the shape corresponding to the shape of the tool electrode is machined. Therefore, as long as the shape of the tool electrode and the tool electrode and the workpiece relative movement between the way, you can work out a variety of complex profiles.          Tool electrodes commonly used good conductivity, high melting point, easy processing of corrosion-resistant materials, such as copper, graphite, copper and tungsten alloy and molybdenum. In the process, the tool electrode is also loss, but less than the amount of workpiece metal removal, and even close to no loss. Working fluid as a discharge medium, also plays a role in the processing of cooling, chip removal and so on. Commonly used working solution is lower viscosity, high flash point, stable performance medium, such as kerosene, deionized water and emulsion.