Superhard cutting tools emerged as a result of the higher requirements for hardness in the processing of modern engineering materials, mainly including diamond cutting tools and cubic boron nitride cutting tools.
Diamond tools have extremely high hardness and wear resistance, and can effectively process non-ferrous metals such as copper and aluminum and their alloys, ceramics, unsintered hard alloys, and various fiber and particle-reinforced composite materials.
Diamond is divided into natural diamond and artificial diamond. Natural diamond deposits have been formed in prehistory, and there is no growth law to follow. Synthetic diamond is a kind of artificially synthesized diamond, which is also resistant to high temperature and high pressure, and is widely used in military industry, aerospace industry, petrochemical industry and other fields.
Introduction to the diamond industry chain: from top to bottom, the diamond industry chain consists of graphite, single crystal, micropowder, polycrystalline composite sheet, and diamond products. At present, about 50% of my country's single crystal is used to produce sawing tools. According to different application fields of polycrystalline products, polycrystalline composite sheets are used in different fields, such as oil exploration, mining, cutting tools, wire drawing die blanks, etc. Diamond products are divided into single crystal products (abrasives, sawing tools) and polycrystalline products (geological drill bits, knives, wire drawing dies). Downstream application fields: Abrasives are mainly used in IC chip processing in the electronic information field, engine processing in the automotive field, air conditioning and refrigerator compressor processing, tool processing, etc.; sawing tools are mainly used in stone industry and construction industry; drilling tools are mainly used in Mine, oil exploitation; tools are mainly used in lathe processing.
Cubic boron nitride, like polycrystalline diamond, is also artificially synthesized under high temperature and high pressure. Its polycrystalline structure and performance are also similar to diamond, with high hardness, good thermal conductivity, and small thermal expansion coefficient. In addition, cubic boron nitride also has excellent chemical and thermal stability, and hardly reacts with iron group elements, which is better than diamond.
Compared with diamond, cubic boron nitride has higher thermal stability, greater chemical inertness to iron group elements, and strong anti-bonding ability. It is more suitable for processing various hardened steels, thermal spray materials, chilled cast iron and HRC35 and above. Difficult-to-cut materials such as cobalt-based and nickel-based materials.
In industrially developed countries, cubic boron nitride cutting tools have been widely used in machinery processing industries such as automobiles and heavy machinery. Cubic boron nitride tools are suitable for high-speed dry cutting, and can process gray cast iron at speeds above 2000m/min. Cubic boron nitride cutting tools are also widely used in high-speed hard cutting, especially for finishing alloy steel parts on automobile engines, such as gears, gear shafts, bearings, etc. between HRC60-65, and these parts used to rely on Grinding to ensure dimensional accuracy and surface quality. For example, Halnn tools has formed a complete set of hard machining solutions from continuous to intermittent, rough machining to super finishing for the process of replacing grinding with turning, and can also provide customized services for chip breakers and wipers.