Graphite electrodes and graphite product materials have the advantages of high machining accuracy and good surface effects, especially in the machining of mold cavities for precision, complex, thin-walled, and high hardness materials. Compared with copper, graphite electrode materials have advantages such as low consumption, fast discharge speed, light weight, and low coefficient of thermal expansion. Therefore, they are gradually replacing copper electrodes as the mainstream of discharge machining materials.
(1) Fast speed.
The discharge of graphite electrodes is 2-3 times faster than that of copper, and the material is not easily deformed. It has obvious advantages in the processing of thin ribbed electrodes. The softening point of copper is around 1000 ℃, which is prone to deformation due to heating. The sublimation temperature of graphite electrodes and graphite products is about 3650 ℃. In comparison, the thermal expansion coefficient of graphite is only 1/30 of that of copper materials; Graphite machining speed is fast, 3-5 times faster than copper electrode machining speed, with particularly outstanding precision machining speed and high strength. For ultra-high (50-90mm) and ultra-thin (0.2-0.5mm) electrodes, they are not easily deformed during machining. Moreover, in many cases, products need to have a good textured effect, which requires making the electrode as a whole as much as possible. However, there are various hidden corners in the production of the whole common electrode. Due to the easy to repair nature of graphite, this problem is easily solved and the number of electrodes is greatly reduced, which copper electrodes cannot achieve.
(2) Lightweight.
The density of graphite electrodes and graphite products is only 1/5 of copper density. When using large electrodes for discharge machining, it can effectively reduce the burden on machine tools and is more suitable for the application of large molds.
(3) Low loss.
Due to the presence of carbon atoms in spark oil, during discharge machining, high temperatures cause the carbon atoms in spark oil to decompose and form a protective film on the surface of the graphite electrode, compensating for the loss of the graphite electrode.
(4) No burrs.
After the copper electrode is processed, it is necessary to manually remove burrs; After processing graphite products, there are no burrs, which not only saves a lot of costs and manpower, but also makes it easier to achieve automated production.
(5) Easy to polish.
Due to the cutting resistance of graphite being only 1/5 of that of copper, manual grinding and polishing are easier to operate.
(6) Low cost.
Due to the continuous increase in copper prices in recent years, the price of graphite is now lower than that of copper in all aspects; For graphite electrodes and graphite products under the same volume conditions, the price of graphite electrode products is 30% -60% lower than that of copper products, and the price is relatively stable, with relatively small short-term price fluctuations.
Post time: 3月-20-2024
