How to make a graphite crucible?

Graphite crucible is a melting container for high-temperature reactions. It is made of graphite material and has good heat resistance and corrosion resistance. It is widely used in chemistry, metallurgy, glass and other fields. Such as melt non-ferrous metals and alloys such as copper, gold, silver, zinc, etc.

The production process

Material selection:

The material for making graphite crucible should be high-purity, high-crystallinity natural graphite or artificial graphite. The carbon content of graphite should be above 99%, and the impurity content should be controlled below 0.2% to ensure the quality and performance of the product.

Physical sintering:

The graphite crucible is made by physical sintering process. First, the graphite material powder is screened to remove impurities and graphite with uneven particles. Then the graphite powder is pressed into the shape of a crucible and sintered at high temperature to form a solid graphite structure.

Precision machining:

The sintered graphite crucible is precision machined. Including appearance finishing, size correction, surface treatment and other processes. Through machining and polishing, it has a smooth appearance, precise size, and is easy to apply and operate.

Inspection and quality control:

Including material composition inspection, sintering uniformity inspection, dimensional accuracy inspection, etc. At the same time, chemical stability tests and high temperature resistance tests are also required to ensure the stability and reliability of the product in high temperature reactions.

Sintering process control:

We need to control the sintering temperature and sintering time to ensure that the crystal structure of the graphite material is properly changed to form a hard structure. At the same time, during the sintering process, attention should also be paid to prevent the deformation and cracking of the graphite crucible, and appropriate measures should be taken to ensure product quality.

Graphitization:

The crucible is energized under high temperature and oxygen-free conditions for graphitization treatment to convert it into a stable graphite structure.

Surface treatment:

This is to improve its corrosion resistance and chemical stability. Common surface treatment methods are impregnation and coating. The impregnation method is to immerse the graphite crucible in a specific liquid to form a protective coating on its surface; the coating method is to apply the coating material to the surface of it to form a protective layer.

Packaging and storage:

After completed, it needs to be packaged and stored to prevent product damage and contamination. Common packaging methods include plastic film packaging, foam protection, etc. During storage, avoid contact with moisture and chemicals, keep dry and clean.

Technical requirements of graphite crucible

The working temperature of the graphite crucible is generally above 1000℃, and the maximum is above 3000℃. Among them, the firing temperature is one of the key factors affecting the quality of it. The higher the firing temperature it, the greater its density, the higher its strength, and the stronger its corrosion resistance. But it will also have a greater impact on the price of it.

Conclusion:

The production process and technical requirements of graphite crucibles include material selection, physical sintering, precision machining, testing and quality control, sintering process control, surface treatment, packaging and storage. So only by strictly controlling the quality and process conditions of each link can we produce graphite crucible products with superior performance and stable quality.