The advantages of graphite electrode are easy to process, high removal rate of EDM and small graphite loss. Therefore, some customers of group based spark machine abandon copper electrode and use graphite electrode instead. In addition, some electrodes with special shape can not be made of copper, but graphite is easier to form, and copper electrode is heavier, which is not suitable for machining large electrode. All these factors lead to the application of graphite electrode in some group based spark machine customers.
The prices quoted by manufacturers of high-purity graphite electrode are different from the design of traditional copper electrode. Many mold factories usually reserve different amount of copper electrode in roughing and finishing, while graphite electrode uses almost the same amount of reserve, which reduces the number of CAD / CAM and machining. This reason alone is enough to improve the accuracy of mold cavity to a large extent.
The aging resistant graphite electrode is mainly made of petroleum coke and needle coke as raw materials and coal asphalt as binder, which is calcined, proportioned, kneaded, pressed, roasted, graphitized and machined. It is a conductor that releases electric energy in the form of electric arc to heat and melt the furnace charge. According to its quality index, it can be divided into ordinary power, high power and ultra-high power.
After copper electrode is transferred to graphite electrode, it should be clear how to use graphite material and other relevant factors. Today, some group based spark machine customers use graphite to discharge machining with electrodes, which avoids the process of mold cavity polishing and chemical polishing, but still achieves the expected surface finish. It is impossible to make such a workpiece without increasing the time and polishing process. In addition, graphite can be divided into different grades. Only by using the appropriate grade of graphite and EDM parameters in a specific application program can the ideal machining effect be achieved. If the operator uses the same parameters as copper electrode in the spark machine using graphite electrode, the result will be disappointing. If the electrode material should be strictly controlled, the graphite electrode can be set in the non loss state (loss less than 1%) during rough machining, but the copper electrode is not used.