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Graphite crucible is widely used in casting but many customers don’t know how to use it correctly. It is very significant for a new made graphite crucible to be conditioned before it is used. Using a graphite crucible correctly includes conditioning and storage. The crucible should be put in an oven at 500 degrees Fahrenheit (260 degrees Celsius) for two hours and then allowed to cool slowly in a dry situation. This keeps moisture from the crucible and prevents cracking. Crucibles should be kept away from moisture and should be re-conditioned if they get wet. A graphite crucible should be cleaned completely when it is done being used. Metal should not be allowed to remain in the crucible to cool.…
Colloidal graphite was first obtained by Acheson in nineteenth Century. Raw materials for natural graphite or artificial graphite. There are two methods for producing colloidal graphite: (1) mechanical method. Natural graphite crushed by hydrochloric acid and hydrofluoric acid to remove impurities. Added to the tannic acid in aqueous solution by repeated decantation into paste. Adding a certain proportion of water and ammonia, and then by ultrasonic treatment to further reduce the particle size, you can get colloidal graphite. (2) chemical method. After purification and crushing of natural graphite, adding concentrated nitric acid and concentrated sulfuric acid and water at 90 degrees Celsius, and then cleaning, drying, adding water, ethanol, acetone and other dispersing agent that is colloidal graphite. Addition of…
At present, the graphite mould is widely used in the following aspects: Graphite mould for continuous casting and semi continuous casting of graphite mould In recent years, the domestic and foreign is to promote the state of molten metal directly from the continuous (or semi continuous) production of rods or tubes, and other advanced production methods. Domestic copper, copper alloy, aluminum, aluminum alloy and other aspects have begun to use this method. Artificial graphite is considered as the most suitable material for continuous casting or semi continuous casting of nonferrous metals. Production practice has proved that due to the adoption of the graphite mold, because of its thermal conductivity is good (thermal conductivity determines the solidification rate of metal or…
