Cubic boron nitride (CBN) is a new type of artificially synthesized material developed in the 1950s. It has high hardness and good wear resistance, and has a wide range of applications in the mechanical processing industry.
Cubic boron nitride is synthesized from hexagonal boron nitride and catalyst under high temperature and pressure, and is another new type of product that emerged after the advent of synthetic diamond. It has high hardness, thermal stability, chemical inertness, as well as excellent properties such as good infrared transmittance and wide bandgap. Its hardness is second only to diamond, but its thermal stability is much higher than diamond, and it has significant chemical stability to iron-based metal elements. The grinding performance of cubic boron nitride grinding tools is excellent, not only capable of processing difficult to grind materials and improving productivity, but also effectively improving the grinding quality of workpieces. The use of cubic boron nitride is a major contribution to metal processing, leading to revolutionary changes in grinding and the second leap in grinding technology.
Polycrystalline cubic boron nitride has a high hardness, reaching 2700-5000HV, second only to diamond hardness; The flexural strength and fracture toughness are between those of hard alloys and ceramics; The thermal stability is much higher than that of synthetic diamond, and it can still be cut at 1300 ℃. It has high oxidation resistance and does not produce oxidation at 1000 ℃. The chemical inertness of iron element is also much greater than that of synthetic diamond, and it is not easy to chemically react with iron-based materials at high temperatures of 1200 to 1300 ℃. However, it will hydrolyze with water at around 1000 ℃, causing a large amount of CBN to be worn. Therefore, when using PCBN cutting tools for wet cutting, attention should be paid to selecting the type of cutting fluid. Therefore, cubic boron nitride, as a superhard tool material, can be used to process black metals such as steel and iron, especially difficult to machine materials such as high-temperature alloys, hot steel, and cold hard cast iron. It is also very suitable for CNC machine tool processing.
The grinding performance of cubic boron nitride grinding tools is excellent, not only capable of processing difficult to grind materials, improving productivity, but also conducive to strict control of the shape and dimensional accuracy of workpieces. It can effectively improve the grinding quality of workpieces, significantly improve the surface integrity of ground workpieces, thus improving the fatigue strength of parts, extending their service life, and increasing reliability. In addition, the production process of cubic boron nitride grinding tools is better than that of ordinary grinding tools in terms of energy consumption and environmental pollution. Therefore, expanding the production and application of cubic boron nitride grinding tools is an inevitable trend in the development of the mechanical industry.
- Grinding and rough grinding of cutting tools made of tungsten, tungsten molybdenum, and other high-speed steels, especially vanadium alloy steel, cobalt alloy steel, and special high-speed steel.
- Precision grinding and final grinding of precision parts made of heat-resistant steel, stainless steel, and high hardness alloy structural steel. These parts cannot achieve high precision when using ordinary grinding tools due to the rapid consumption or blunting of the tools.
- Grinding of various material parts sensitive to local thermal stress and thermal shock.
- Precision grinding and final grinding of large precision workpieces (machine tool guides, high-precision machine tool screws). These workpieces often experience significant thermal deformation due to high grinding temperatures, resulting in failure to achieve high precision.
- Precision grinding and final grinding of workpieces (instruments and micro bearings) produced in large quantities on automatic and semi-automatic machine tools.
- Grinding of complex surface workpieces (hobbing cutters, pulling cutters, high-precision gears, molds, punches) that require grinding tools with good edge retention.
- Surface grinding of thread cutting tools and thread gauges (taps, thread rollers, thread plugs, etc.).
- Ultra precision machining of heat-resistant steel workpieces that are difficult to process.
- Grinding of other steel quenching tools
