Introduction to the properties of polycrystalline diamond

Polycrystalline Diamond(PCD) Performance Introduction

(1) High hardness and wear resistance
The hardness of polycrystalline diamond is as high as about 10000HV, which is the hardest material in the world's artificial materials at present, much higher than that of cemented carbide and engineering ceramics. Because of its high hardness and isotropy, polycrystalline diamond has excellent wear resistance.

(2) Low friction coefficient
The friction coefficient between polycrystalline diamond and some non-ferrous metals is lower than that of other materials, about 1/2 of that of cemented carbide. The low friction coefficient not only reduces the deformation and cutting force, but also does not produce chip build-up during cutting, thus reducing the machined surface roughness.

(3) High thermal conductivity
The thermal conductivity of polycrystalline diamond is very high, better than that of silver and copper, and much higher than that of ordinary cemented carbide. Therefore, the cutting heat is easy to dissipate during the cutting process, so the cutting temperature is low.

(4) High machining accuracy
Due to the low thermal expansion coefficient and high elastic modulus of polycrystalline diamond tool, the tool is not easy to deform during the cutting process. Under the action of cutting force, the tool can maintain its original parameters, keep sharp for a long time, and have high cutting accuracy. So when PCD tool is used for machining, it can reduce cutting force and cutting temperature, improve tool durability and cutting rate, and obtain good machining surface.

Main problems: The high hardness and wear resistance of PCD materials make it very difficult to form and finish the surface, which seriously hinders its popularization and application.

Common processing methods: EDM, laser processing, chemical processing, ultrasonic processing.
Ideal processing method: grinding or grinding.

 

Polycrystalline diamond (PCD) is a new type of superhard material that has been studied and used internationally since the 1970s. It is sintered at high temperature of 1400 ℃ and high pressure of 6GPa.

Polycrystalline diamond is not only an engineering material, but also a new type of functional material; It is not only a high-tech product, but also a cost-effective product. With the development of modern industry and science and technology, polycrystalline diamond has been increasingly widely used in modern industry, national defense and high-tech fields due to its excellent mechanical, thermal, chemical, acoustic, optical and electrical properties.