PCD is made of specially treated diamond and a small amount of binder sintered under high temperature and high pressure. The disorderly arranged diamond grains make PCD have uniform, extremely high hardness and wear resistance. PCD can be used for cutting tools, grinding wheel, geological drilling, wire drawing molds, sandblasting molds, etc.

The grinding process of PCD is mainly the result of the mixed action of mechanical and thermochemical aspects. The mechanical action is the micro-cracking, abrasion, shedding or cleavage of the diamond formed by the continuous impact of the diamond grinding wheel grains on the PCD material. The thermochemical action is the high temperature formed by the diamond grinding wheel grinding PCD to oxidize or graphitize the diamond. The result of the mixed action of the two causes the PCD material to be removed. The main characteristics of the grinding process are:

(1) Great grinding force

Diamond is the material with the highest hardness among known minerals. The amount of wear when matched with various metal and non-metal materials is only 1/50～1/800 of cemented carbide. The hardness of PCD is second only to single crystal diamond and much higher than cemented carbide. When using a diamond wheel to grind PCD, the initial cutting strength is very high, about 10 times that of cemented carbide (0.4MPa). Therefore, the grinding force is much higher For grinding cemented carbide.

(2) Small grinding ratio

Due to the high hardness and wear resistance of PCD, the grinding ratio when grinding PCD is only 0.005～0.033, which is about 1/1000～1/100000 of cemented carbide. Therefore, in order to ensure the quality and removal of the cutting tool's edge, the grinding time is very long and the processing efficiency is very low. In addition, when the hardness, content and particle size of PCD are different, the grinding time is also very different.

(3) Granularity has a great influence

PCD materials used for cutting tools are mainly divided into three categories according to the particle size: coarse particle size (20-50μm), medium particle size (about 10μm) and fine particle size (~5μm). The grinding force and grinding ratio are different from several times to dozens times. Coarse particle size of PCD has the highest grinding ratio and the most difficult to grind. After grinding, the cutting edge has the worst serration and worst quality, but it has the strongest wear resistance. Fine particle size of PCD has the relatively lowest grinding ratio and is easier to grind. The cutting edge quality is the best after grinding.