Graphite crucible is a kind of refractory graphite crucible which is made of crystalline natural graphite as main material, plastic refractory clay as the binder, and with different types of clinker. It is mainly used for smelting special alloy steel, melting non-ferrous metals and their alloys. Graphite crucibles are an integral part of refractories materials according to its properties and application.
In graphite crucible, there are three kinds of common graphite crucible and special allotypic graphite crucible and high purity graphite crucible. Different types of graphite crucibles are different from raw materials, production methods, process technology and product type specifications due to their different performances, application and conditions.
The main raw material of graphite crucible is crystalline natural graphite. Therefore, it keeps all kinds of physical and chemical properties of the natural graphite. That is to say, it has good thermal conductivity and high temperature resistance, and the thermal expansion coefficient is small in the process of high temperature application, and it has a certain anti strain property to the rapid heating and rapid cooling. The corrosion resistance of acid and alkaline solution is strong, and it has excellent chemical stability.
The graphite crucible has many types and specifications, and it is not limited by the production scale, batch size and smelting material variety when we use them. It can be chosen arbitrarily, and it has strong applicability and can ensure the purity of the melted material.
Graphite crucible is widely used in smelting of alloy tool steel and the smelting of nonferrous metals and their alloys and it has better technical and economic effects because of their excellent properties.
The production materials of graphite crucible can be summarized into three types. The first is crystalline natural graphite, the second is plastic refractory clay, and the third is calcined hard kaolin skeleton clinker. In recent years, the high temperature resistant synthetic materials such as silicon carbide, alumina, carborundum and ferrosilicon have been used as the framework clinker. This kind of clinker has remarkable effect on improving the quality of crucible product, enhancing the density and mechanical strength of crucible.
There are three kinds of forming methods for graphite crucible which are hand molding,the rotary plastic forming method and the pressing forming method