Several preparation methods of boron nitride

Preparation method of boron nitride

1. Chemical vapor synthesis

In 1979, Sokolovsky successfully prepared cubic boron nitride (CBN) films using pulsed plasma technology at low temperature and low pressure. The equipment used is simple and the process is easy to realize, so it has been developed rapidly. A variety of vapor deposition methods have emerged. Traditionally, it mainly refers to thermal chemical vapor deposition. The experimental device is generally composed of a heat-resistant quartz tube and a heating device. The substrate can be heated by a furnace (hot wall CVD) or high frequency induction heating (cold wall CVD). The reactive gas decomposes on the surface of the high-temperature substrate, and at the same time, a chemical reaction occurs to deposit a film. The reaction gas is a mixed gas of BCl3 or B2H4 and NH3.

2. Hydrothermal synthesis

In this method, water is used as the reaction medium in the high temperature and high pressure reaction environment in the autoclave to dissolve insoluble or insoluble substances, and the reactants can also be recrystallized. The hydrothermal technology has two characteristics, one is that the temperature is relatively low, and the other is that it is carried out in a closed container to avoid volatilization of the ingredients. As a low-temperature and low-pressure synthesis method, it is used to synthesize cubic boron nitride at low temperature.

3. Benzene thermal synthesis

As a low-temperature nanomaterial synthesis method that has emerged in recent years, benzene thermal synthesis has received extensive attention. Due to its stable conjugated structure, benzene is an excellent solvent for solvothermal synthesis. Recently, it has been successfully developed into benzene thermal synthesis technology, such as reaction formula:

BCl3+Li3N→BN+3LiCl

BBr3+Li3N→BN+3LiBr

The reaction temperature is only 450°C, and the benzene thermal synthesis technology can produce a metastable phase that can only be prepared under extreme conditions at relatively low temperature and pressure, and can only exist under ultra-high pressure. The method realizes the preparation of cubic boron nitride at low temperature and low pressure. However, this method is still in the experimental research stage, and it is a synthetic method with great application potential.

4. Self-propagating technology

The necessary energy from the outside is used to induce a highly exothermic chemical reaction, and the local reaction of the system forms a chemical reaction front (combustion wave). The chemical reaction proceeds quickly with the support of its own exothermic heat, and the combustion wave propagates throughout the system. Although this method is a traditional inorganic synthesis method, the synthesis of boron nitride has only been reported in recent years.

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 2000°C, and depending on the brand, its dielectric strength is close to 1000 volts/mil. Boron nitride is hot-it is pressed as a blank and can be easily processed into bars, bars, plates and even custom shapes.

Application of Boron Nitride

1. Metal forming release agent and metal drawing lubricant.

2. Special electrolytic and resistance materials under high temperature conditions.

3. High-temperature solid lubricants, extrusion anti-wear additives, ceramic composite materials production additives, refractory materials and antioxidant additives, especially additives resistant to molten metal corrosion, heat-resistant additives, high-temperature insulating materials.

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

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

6. Aerospace thermal shielding materials.

7. With the participation of a catalyst, it can be converted into cubic boron nitride with hardness like diamond after high temperature and high pressure treatment.

8. The structural materials of the atomic reactor.

9. Airplane and rocket engine nozzles.

10. High-voltage and high-frequency electrical insulators and plasma arc insulators.

11. Packaging materials to prevent neutron radiation.

12. The superhard materials made by boron nitride processing can be made into high-speed tools and drill bits for geological exploration and oil drilling.

13. Metallurgical continuous casting steel isolation ring, amorphous iron launder, continuous casting aluminum mold release agent (various optical glass mold release agents)

14. Production of evaporation boats for various capacitor film aluminum plating, picture tube aluminum plating, display aluminum plating, etc.

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

16. Various laser anti-counterfeiting aluminum plating, brand hot stamping materials, various cigarette labels, beer labels, packaging boxes, cigarette packaging boxes, etc.

17. The lipstick filler used in cosmetics is non-toxic, lubricious and shiny.

In terms of optical applications, due to the high hardness of the c-BN film, it has high transmittance in the entire wavelength range from ultraviolet (about 200nm) to far infrared. It is suitable as a surface coating for some optical components, especially for zinc selenide ( Coating of window materials such as 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 applications. detector.

Boron Nitride Price

The price of boron nitride will vary randomly with the production cost, transportation cost, international situation, exchange rate and supply and demand in the boron nitride market. Tanki New Materials Co.,Ltd. aims to help various industries and chemical wholesalers find high-quality, low-cost nanomaterials and chemicals by providing a full set of customized services. If you are looking for boron nitride, please feel free to send an inquiry to get the latest price of boron nitride.

Boron Nitride Supplier

As a global boron nitride supplier, Tanki New Materials Co.,Ltd. has extensive experience in the performance, application and cost-effective manufacturing of advanced engineering 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.