Bring you knowledge of boron nitride BN powder

What is boron nitride?

Boron nitride was introduced more than 100 years ago. The earliest application was hexagonal boron nitride as a high temperature lubricant. h-BN not only has a structure, but its properties are very similar to graphite, and it is white, so it is usually called white graphite.

Boron nitride is a crystal composed of nitrogen atoms and boron atoms. The chemical powder consists of 43.6% boron and 56.4% nitrogen, and has four different variants: hexagonal boron nitride (HBN), rhombohedral boron nitride (RBN), cubic boron nitride (CBN) and wurtz Mineral Boron Nitride (WBN).

Cubic boron nitride is usually black, brown or dark red crystals and is a zinc blende structure with good thermal conductivity. Hardness is second only to diamond, it is a kind of super hard material, usually used as tool material and abrasive.

Hexagonal boron nitride has extremely low friction coefficient, excellent high temperature stability, good thermal shock resistance, high strength, high thermal conductivity, small expansion coefficient, high resistivity, corrosion resistance, microwave penetration or infrared penetration Permeability.

Preparation method of boron nitride

The boron nitride that is usually produced has a graphite-type structure, which is commonly referred to as white graphite. The other is the diamond type, which is similar to the principle of converting graphite into diamond. Graphite-type boron nitride can be converted into diamond-type boron nitride under high temperature (1800°C) and high pressure (8000 MPa) [5-18 GPa]. It is a new type of high temperature resistant superhard material used in the production of drill bits, grinding tools and cutting tools.

There are several methods for preparing boron nitride: high temperature and high pressure synthesis, chemical vapor synthesis, hydrothermal synthesis, benzene thermal synthesis, self-propagating technology, carbothermic synthesis technology, ion beam sputtering technology, laser. Induced reduction method.

Hydrothermal technology has two characteristics, one is its relatively low temperature, and the other is in a closed container to avoid evaporation of ingredients. As a low-temperature and low-pressure synthesis method, it is used to synthesize cubic boron nitride at low temperatures.

In 1979, Sokolovsky successfully used pulsed plasma technology to prepare boron nitride (CBN) films at low temperature and low pressure. The equipment used is simple and the process is easy to implement, so it has been developed rapidly. A variety of vapor deposition methods have emerged, traditionally referred to as thermal chemical vapor deposition.

Future prospects of boron nitride

Due to the high hardness of steel, a lot of heat is generated during processing. Diamond tools are easy to decompose and react effectively with transition metals at high temperatures, while c-BN materials have good thermal stability and are not easy to produce with iron group metals or alloys. This reaction can be widely used in precision machining and grinding of steel products.

In addition to excellent wear resistance, c-BN also has excellent heat resistance. It can also cut heat-resistant steel, ferroalloy, hardened steel, etc. at higher cutting temperatures, and can cut high-hardness cold rolls and leaks. The carbon quenching material and Si-A1 alloy have very large wear on the tool. In fact, tools and grinding tools made of c-BN crystal sintered body (high temperature and high pressure synthesis) have been used in high-speed precision machining of various cemented carbide materials.

In optical applications, c-BN film has high hardness and high transmittance from ultraviolet (approximately 200 nm) to far infrared, so it is suitable for use as a surface coating for certain optical components. Coating of window materials, such as zinc selenide (ZnSe) and zinc sulfide (ZnS). In addition, it has good thermal shock resistance and quotient hardness, and is expected to become an ideal window material for high-power lasers and detectors.

c-BN is the third-generation semiconductor material with the best performance. It can not only be used in the production of electronic equipment that works under extreme conditions such as high temperature, high frequency, and high power, but also has broad application prospects in deep ultraviolet luminescence and detectors. In fact, Mishima et al. It is first reported that c-BN LEDs manufactured under high temperature and high pressure conditions can work at a temperature of 650°C.

Under forward bias, the diode emits visible blue light, and spectral measurements show that it is the shortest. The wavelength is 215 nm (5.8 eV). C-BN has a thermal expansion coefficient similar to GaAs and Si, high thermal conductivity and low dielectric constant, good insulation properties and good chemical stability, making it an insulating coating for heat sink materials and integrated circuits. In addition, C-BN has a negative electron affinity and can be used as a cold cathode field emission material, which has broad application prospects in the field of large-area flat-panel displays.

Overview of Boron Nitride

Boron nitride industrial powder is a pure white ceramic material with a hexagonal crystal structure similar to graphite. Boron nitride can withstand temperatures exceeding 2,000°C, and its dielectric strength is close to 1000 volts/mil depending on the grade. Boron nitride is very hot and pressed in the form of blanks, which can be easily processed into rods, bars, plates and even customized shapes.

Application of Boron Nitride

1. Mold release agent for metal forming and lubricant for metal wire drawing.

2. Special electrolytic resistance materials under high temperature conditions.

3. High-temperature solid lubricants, extrusion anti-wear additives, additives used in the production of ceramic composites, refractory materials and antioxidant additives, especially in the case of molten metal corrosion resistance, heat-reinforcing additives, high-temperature insulating materials.

4. Heat-sealing desiccant for transistors and additives for polymers such as plastic resins.

5. Pressed into various shapes of boron nitride products, which can be used as parts for high temperature, high pressure, insulation and heat dissipation.

6. Aerospace thermal shielding materials.

7. With the participation of catalysts, it can be transformed into cubic boron nitride, which is as hard as diamond, after high temperature and high pressure treatment.

8. The structural materials of the atomic reactor.

9. Aircraft, rocket engine nozzles.

10. High voltage, high frequency electricity and plasma arc insulators.

11. Packaging materials to prevent neutron radiation.

12. The superhard materials processed by boron nitride are made into high-speed cutting tools and drill bits, which are used for geological prospecting and oil drilling.

13. Continuous cast steel isolation ring for metallurgy, amorphous iron launder, continuous cast aluminum release agent (various optical glass release agents)

14. Production of various evaporation boats, used for aluminum plating of capacitor films, aluminum plating of picture tubes, aluminum plating of displays, etc.

15. All kinds of fresh-keeping aluminum packaging bags, etc.

16. All kinds of laser anti-counterfeiting aluminum plating, brand hot stamping materials, all kinds of cigarette labels, beer labels, packaging boxes, cigarette packaging boxes, etc.

17. The fillers used in lipstick cosmetics are non-toxic, lubricious and shiny.

In optical applications, due to the high hardness of c-BN film and the high transmittance of the entire wavelength range from ultraviolet (approximately 200 nm) to far infrared, it is suitable for use as a surface coating for certain optical components, and is particularly suitable for use as Coating of window materials such as zinc selenide (ZnSe) and zinc sulfide (ZnS). In addition, it also has good thermal shock resistance and hardness, and is expected to become an ideal window material for high-power lasers and high-power lasers. detector.

Boron Nitride Price

The price of boron nitride will vary randomly with production costs, transportation costs, international conditions and market supply and demand of boron nitride. Tanki New Materials Co. Ltd aims to help all industries and chemical wholesalers find high-quality products by providing a full range of products. Tailor-made services, low-priced nanomaterials and chemicals. If you are looking for boron nitride, please feel free to send an inquiry to get the latest price of boron nitride.

Suppliers of Boron Nitride

As a global boron nitride supplier, Tanki New Materials Co. Ltd has extensive experience in the performance, application and cost-effective manufacturing of advanced and engineered materials. The company has successfully developed a series of powder materials (titanium nitride, silicon nitride, titanium nitride, etc.), high-purity targets, functional ceramics and structural devices, and provides OEM services.