At the cutting edge of modern industry, polycrystalline diamond compacts (PCD) are undoubtedly a shining gem. This functional material, formed by sintering diamond micropowder onto a cemented carbide substrate under ultra-high pressure and temperature, is not merely a physical mixture, but a perfect marriage of materials science. It possesses both the extreme hardness and wear resistance of diamond, as well as the toughness and impact resistance of cemented carbide.

Unrivalled Core Advantages

The core competitiveness of PCD lies in its outstanding comprehensive performance. 

Firstly, hardness is paramount. With a Vickers hardness of 7,500 to 9,000—second only to natural diamond—it is isotropic, eliminating the need for orientation selection required in single-crystal diamond. More crucially, it overcomes the fatal weakness of single-crystal diamond: its brittleness. The diamond grains within PCD are arranged in a disordered pattern with no cleavage planes; when subjected to impact, they undergo only micro-grain fracturing rather than large-scale fragmentation, endowing it with exceptional impact resistance.

Secondly, it exhibits excellent friction and thermal conductivity properties. The coefficient of friction between PCD and non-ferrous metals is only 0.1 to 0.3, approximately half that of cemented carbide, significantly reducing cutting forces and temperatures. At the same time, its thermal conductivity reaches as high as 146 W/m·K, which is 1.5 to 7 times that of cemented carbide, enabling rapid dissipation of cutting heat and preventing tool overheating and softening. Furthermore, its extremely low coefficient of thermal expansion ensures machining accuracy, making it perform exceptionally well in precision machining.

Wide-ranging and extensive applications

Thanks to the advantages outlined above, PCD has become the undisputed workhorse in the drilling and cutting sectors.

In geological and petroleum drilling, PCD is the undisputed leader. Compared to traditional carbide drill bits, PCD drill bits offer a service life that is 10 to 30 times longer, whilst increasing mechanical drilling speed by 30% to 40%. With their strong self-sharpening properties, they maintain a sharp cutting edge at all times, making them particularly suitable for soft to medium-hard formations. Today, from deep-sea oil and gas extraction to mineral exploration, PCD teeth vertically brazed onto drill bits are fracturing rock with astonishing efficiency.

In the fields of machining and high-end manufacturing, PCD is redefining cutting standards. In automotive manufacturing, it is used to machine wear-resistant components such as engine pistons and cylinder blocks; in the aerospace sector, it serves as the key cutting tool for machining highly hard and brittle materials. For non-ferrous metals such as aluminium and copper, as well as non-metallic materials including graphite, plastics and wood, PCD tools offer durability dozens of times greater than that of cemented carbide, whilst achieving an extremely low surface roughness. Furthermore, they are widely used in wire drawing dies, enabling precise control of wire dimensions and delivering an exceptionally high surface finish.

In emerging technology sectors, PCD demonstrates immense potential. With technological advancements, composite plates featuring diamond layers thickened to 2–4 millimetres, as well as specially shaped composite plates (such as helmet-shaped and ridge-shaped designs), are continually being developed. These innovations not only enhance impact resistance but also excel in high-end applications such as semiconductors and new energy, where they are utilised for precision and ultra-precision machining.