Mold in the home appliance, automobile, mechanical and electrical, aerospace and other industrial fields are increasingly becoming the main production process of industrial mass production equipment, undertake the processing of these products in the industry 60%-90% production. In recent years, the high speed milling has broken through the limitation of the traditional milling, which is difficult to process the material with high hardness, high strength and high toughness. But the EDM has high machining accuracy and surface quality, machining range, especially in the complex and precise, thin-walled, narrow, mold processing high hard materials in the advantage of high speed milling cannot be compared, so the electric discharge machining will be the main means of mould cavity machining. The graphite electrode (compared with copper) electrode consumption, discharge machining speed, good machining performance, light weight, small thermal expansion coefficient and other advantages.Compared with copper, graphite electrode has the advantages of less consumption, high discharge rate, light weight and low thermal expansion coefficient.
Speed: Graphite discharge is 2-3 times faster than copper material, not easy to deformation, obvious advantages in the processing of thin electrodes, copper softening point at about 1000 degrees, easily deformed by heat, graphite sublimation temperature is about 3650 degrees, compared with graphite material thermal expansion coefficient of copper is only 1/30;
Light weight: the density of the graphite is only 1/5 of the copper, large electrode discharge processing, can effectively reduce the burden of machine tools (EDM), more suitable for large mold applications;
The loss is small: due to the C atom in the spark oil, in the process of discharge, high temperature causes the C atoms in the spark oil to be decomposed, and the protective film is formed on the surface of the graphite electrode
Low cost: due to rising copper prices in recent years, today, the price of copper than the isotropic graphite graphite products are lower; the same volume and the price is lower than copper in thirty percent to sixty, the price is relatively stable, short-term price fluctuations are relatively small.
