The reason why graphite molds are utilized in this form of manufacturing is due to the fact that graphite as a material has a rather high melting point of 4200 K or around 6,422 degrees Fahrenheit.
This high melting point is important as the molds are typically filled with materials that are in a molten state, meaning the molds must be able to withstand high temperatures which melt other materials. A graphite mold is typically made from two-pieces which fit together tightly with an opening towards the top where the molten material of your choice can be poured into once the mold is filled the material is allowed to cool which results in a final product or a product that is ready for secondary finishing steps.
Finding the right graphite manufacturer can be harder than it seems, as you will typically have to search through manufacturers who do this type of permanent molding in order to receive a product that fits your needs and the requirements of your application. A well-made graphite mold is the first step to making the perfect final product; a poorly constructed graphite mold means that the final product may have some flaws or imperfection that may impact the final application of that product.
There are a number of different ways in which graphite molds are utilized from gravity filling by simply pouring in a molten material which is the simplest and typically most cost effective method, to a more in-depth process such as pressure based filling of the mold in order to preserve the finer details within the mold. This process takes a bit longer and cost a bit more, but results in a more detailed and specific final product.
Whatever your final application or desired final product is, is what dictates what type of graphite mold process is used by the manufacturer of your choice. It is important to relay the specifications and requirements of your application to the mold manufacturer so they can construct a graphite mold that will fit all of your needs and wants.