Graphite mold is mostly carbon, part of the air so that the graphite prone to oxidation at high temperatures, Typically graphite oxide at about 500 ℃ start, and with the graphite mold temperature increases the oxidation rate of oxidation of geometric growth intensified.Graphite mold is mainly graphite machining, and the periphery of each of the carbon atoms linked to three other carbon atoms covalently bonded to constitute a covalent molecule.
Graphite mold has been used following areas:
1. artificial graphite die for hot pressing sintering of cemented carbide has the following characteristics: if pressed when the temperature increased to 1350-1450 degrees, the pressure can be reduced to the desired unit 67- 100 kg / sq cm (that is, cold pressure of 1/10) can;
2. graphite mold has been successfully applied on centrifugal casting . In order to prevent the burning of artificial graphite mold, oxidation can take certain measures .
3. molten metal directly continuous (or semi-continuous) bar or tube manufacturing and other advanced production methods. Artificial graphite as a non-ferrous metal continuous casting or semi-continuous casting mold is considered the most suitable material.This not only greatly improve the yield, reduce scrap loss, and product quality has greatly improved.
4. artificial graphite material has been used successfully on non-ferrous metals pressure casting . pressure die casting production of zinc alloy and copper alloy castings artificial graphite materials have been used in automotive parts and so on.
5. Since the graphite material having chemical stability, less susceptible to the infiltration of molten glass, does not change the composition of the glass, good thermal shock resistance graphite material, size and other characteristics with temperature change is small, manufacture become an indispensable mold material, can be used to manufacture the glass tube, pipe, and so on.
6. the use of artificial graphite material minimal thermal deformation characteristics of transistors can be manufactured sintering mold and brackets, has been widely used,. the graphite mold is also used in cast iron mold, the durability of the mold with a variety of non-ferrous metals. Diamond Mold requires high material hardness and good oxidation resistance, high precision machining, using high-quality raw materials, graphite molds greatly extended life and improved oxidation resistance. Hot sintered diamond tools graphite mold, charged with the dual role of the heating element and the mold support in the diamond tool manufacturing process, graphite mold quality will directly affect the dimensional accuracy and appearance of the shape of diamond tools and so on. Under working conditions, require both heat generating element and forming a graphite mold having conductivity, high electrical resistivity, adequate mechanical strength, but also it has good oxidation resistance and long life, in order to ensure the diamond dimensional accuracy and high performance tools.