For some applications like in the semiconductor industry, a high purity of the graphite material is needed. To reach this high quality, NKCG offers the possibility to purify the graphite pieces after machining.
The purification of a graphite piece consists to remove the impurities (elements else than carbon) without modifying the integrity or properties of the pieces.
This can be performed by heating the graphite under a constant flow of carrier gas. Higher purity can also be obtained using chlorinated or fluorinated gas. These gases will react with the impurities and form with it a volatile compound that can diffuse out of the graphite.
Depending on the need of our customers, different process can be used (high temperature with or without reactive gases). This will lead to different end-purities of the graphite pieces.