Graphite has the versatility to machine very large to small precision sizes. Graphite electrodes offer excellent cutting performance and produce fewer burrs and similar issues, thereby enabling speed improvements in both cutting and EDM processes.
Dies have become the main process equipment for industrial mass production in the industrial fields such as home appliances, automobiles, electromechanics, and aerospace, and have taken over 60%-90% of the parts and components in these industries. In recent years, high-speed milling has broken through the limitations of traditional milling that is difficult to machine high-hardness, high-strength, high-toughness mold materials. However, EDM has the advantages of high machining accuracy, high surface quality, and a wide range of machining. The advantages of high-speed milling, especially in the machining of complex, precise, thin-walled, narrow-slot, high-hard material mold cavities, are unmatched. Electro-discharge machining will remain the main tool for mold cavity machining. Because the graphite electrode (compared to copper) has the advantages of low electrode consumption, high discharge machining speed, good mechanical processing performance, light weight, and small thermal expansion coefficient, gradually replacing the copper electrode becomes the mainstream of the electro-processing electrode.
Compared with copper, graphite electrodes have the advantages of less consumption, faster discharge speed, lighter weight, and smaller thermal expansion coefficient. Therefore, the replacement of copper electrodes gradually becomes the mainstream of discharge processing electrodes. In contrast, graphite electrode materials have the following advantages:
Fast speed: graphite discharge is 2-3 times faster than copper, the material is not easy to be deformed, the advantage is obvious in the processing of thin-bar electrode, the softening point of copper is about 1000 degrees, easily deformed by heat, the sublimation temperature of graphite is 3650 degrees. In contrast, the coefficient of thermal expansion of graphite materials is only 1/30 that of copper;
Light weight: The density of graphite is only 1/5 of that of copper. When the large electrode is used for electric discharge machining, it can effectively reduce the burden on the machine tool (EDM), and is more suitable for the application of large-scale molds;
Low loss: Since the spark oil contains C atoms, during the electrical discharge machining, the high temperature causes the C atoms in the spark oil to be decomposed, and a protective film is formed on the surface of the graphite electrode to compensate the loss of the graphite electrode;
Burr-free: After the copper electrode is processed, it is still necessary to remove the burrs manually, and there is no burr after the graphite processing, which not only saves a lot of cost and manpower, but also makes it easier to achieve automatic production;
Easy to polish: As the cutting resistance of graphite is only 1/5 of that of copper, it is easier to operate by hand to grind and polish.
Low cost: Due to rising prices of copper materials in recent years, the price of same-sex graphite is lower than that of copper. The price of graphite products in the same volume is 30% to 60% lower than that of copper, and the price is relatively stable. Short-term price fluctuations are relatively small.
With high tech and abundant experience, XRD Graphite keep supplying many different customers with our EDM graphite products. We demand unwavering focus on quality and reliable delivery.
Here is physical and chemical index of graphite material：http://www.graphitemachining.cn/materials