Diamond material cutting tools have extremely high hardness and abrasive resistance, and can effectively process non-ferrous metals such as copper and aluminum and their alloys, ceramics, unsintered carbides, various fiber and particle reinforced composite materials etc. Natural diamond deposits have been formed in prehistoric times and there is no growth rule to follow. Synthetic diamond is mainly used in the military industry and aerospace industry because it is resistant to high temperatures and high pressures. It is required for astronauts' helmet membrane, the heat shield of the spacecraft, and high-speed rail sleepers etc. Synthetic diamonds are also widely used in advanced manufacturing and modern processing industries, from dental implants, bone-knifes in cosmetic hospitals, to automotive bearings and electronic components. Large corrugated sheets inlaid with synthetic diamonds can be used to cut huge stones and road cement, and also play an important role in geological exploration and oil exploration.
From the top to the bottom, the diamond industry chain is graphite, single crystal, micro powder, polycrystalline composite sheet, and diamond products etc. Currently, about 50 percent of single crystals are used in the production of sawing tools. Polycrystalline composite sheets are further divided into: oil-opening, mine opening, cutting tools, and wire drawing die blanks etc. Diamond products are further divided into single crystal products (abrasive tools, sawing tools, cutting tools etc.), polycrystalline products (geological drill bits, cutting tools, wire drawing die blanks etc.).
Like diamond, cubic boron nitride is also artificially synthesized under high temperature and high pressure. Its polycrystalline structure and properties are similar to those of diamond, it has high hardness, good thermal conductivity, small thermal expansion coefficient, small density and lower fracture toughness. In addition, cubic boron nitride also has excellent chemical and thermal stability, hardly reacts with iron elements, which is superior to diamond. Compared with diamond, cubic boron nitride has higher thermal stability, strong chemical inertness to iron group elements, strong anti-bonding ability, and is more suitable for processing various quenched steel, thermal spraying materials, chilled cast iron, hardness more than HRC35. hard-to-cut materials such as cobalt-based and nickel-based. In industrialized countries, cubic boron nitride tools have been widely used in automotive, heavy machinery and other mechanical processing industries. The cubic boron nitride cutting tools is suitable for high-speed dry cutting, and can process gray cast iron at a high speed of 2000 mm/min or higher. Cubic boron nitride tools are also widely used in high-speed hard cutting, especially for alloy steel parts on finished engine, such as gears, shafts and bearings between HRC60-65. These components used to rely on grinding to ensure size accuracy and surface quality.
As we all know, the main component of cemented carbide inserts is tungsten carbide, and tungsten is a scarce resource. According to the current development and use level, tungsten carbide resources will be rapidly reduced. Some experts predict that in the next few decades, it may be exhausted. So new superhard material tools will play a bigger role in the future cutting field.