The coating material of PCD tools must have high hardness and high wear resistance, as well as stable chemical properties. It is generally difficult for a single PCD tool coating material to have the necessary performance. Therefore, coating materials of hard PCD tool have moved from a single TiC and TiN to a new stage of developing multiple coatings. The newly developed PCD tool coating not only improves the toughness of the coating and the bonding strength of the substrate, but also improves the wear resistance of the PCD tool coating. The PCD tool coating technology not only breaks through the diamond film coating technology on the cemented carbide substrate, but also comprehensively improves the performance of the PCD tool.

So far, the most mature and widely used hard coating material in the PCD tool grinding process is TiN, but the bonding strength between TiN and the substrate is not as good as TiC coating, it is easy to peel off the coating, and the hardness is not as high as TiC. When the cutting temperature is high, the film of the PCD tool is easily ablated due to oxidation. TiC coating generally has very high hardness and wear resistance, and its oxidation resistance is the most important, but it is too brittle. Therefore, both TiC and TiN coatings have their own advantages. During the coating process, the chemical properties of TiCN can be controlled by continuously changing the components of C and N, thereby forming a multi-layer structure of different components, improving the toughness of the PCD tool coating, increasing the thickness of the coating, and greatly reduce the chipping phenomenon of PCD grinding tools.

The coating of PCD tools not only determines the characteristics of the tool, but also determines its life. TiCN-based coating is generally suitable for processing materials such as ordinary steel, alloy steel, stainless steel and wear-resistant cast iron. When using it to process these materials, the removal rate can reach more than 3 times the normal removal rate. Therefore, the performance of PCD tool coating is so important in the manufacture and processing of handicrafts.