boron carbide supplier

Our advantage: A single furnace produces 4 tons of finished products, and the first-level finished product rate is more than 70%. The company has developed and produced sub-nano-grade boron carbide with a B4C content of up to 99.5%. It is one of the domestic manufacturers with high-purity boron carbide production capacity. It can mass produce products with a median diameter of 0.5 microns. Products with a median diameter of 0.3 microns can be produced. Introduction and application of boron carbide and its products
Boron carbide is a hard black crystal with metallic luster, commonly known as black diamond. It is a kind of powdered product made by smelting and crushing boric acid and carbon materials in an electric furnace at high temperature. The theoretical density is 2.52g∕cm3, the melting point is 2450℃, and the microhardness is 4950kgf∕mm2. Its hardness is second only to diamond and cubic boron nitride, and belongs to the same superhard material as diamond and cubic boron nitride. It has the characteristics of high temperature resistance, acid and alkali corrosion resistance, high strength, good chemical stability, and light specific gravity. It has been widely used in many new materials. Boron carbide is insoluble in water and organic solvents, has strong chemical stability, is resistant to acid and alkali corrosion, and hardly reacts with all acid and alkali solutions. Boron carbide also has the following characteristics: it has a large thermal neutron capture cross-section, strong neutron absorption capacity, so it is called a neutron absorber; it has semiconductor properties and so on.

History of boron carbide: It was discovered in the 19th century as a by-product of metal boride research and was not scientifically studied until the 1830s. Its Mohs hardness is 9.3, which is the third hardest known substance after boron nitride and diamond.
Uses and characteristics:
⑴ Used in the field of national defense industry:
Manufacture of bulletproof materials, such as bulletproof plates in bulletproof vests, ceramic bulletproof tiles for pilot cockpits of *** aircraft, and ceramic bulletproof plates for modern armored personnel carriers and tanks. It can be used as a nozzle for manufacturing guns and guns in the military industry. At present, AL2O3-based ballistic ceramics have been used in "502 Project" and "212 Project", but when the AL2O3-based ceramic composite armor is used on the side of the tank body and other parts, the weight reduction effect is not obvious, and the same thickness is used. Performance Boron carbide ceramic composite armor is 15%-20% lighter than AL2O3-based bulletproof ceramics, and the ballistic performance is further improved. Therefore, the key equipment engineering ceramic composite armor development project puts forward an urgent need for high-performance, low-cost boron carbide bulletproof ceramics. Therefore, the development and application of high-performance, low-cost boron carbide bulletproof ceramic materials can greatly improve the performance of related military equipment, and have significant military and economic benefits. The application direction of boron carbide bulletproof ceramic materials is: key equipment projects, future main battle tanks, infantry fighting vehicles, airdrop and airborne vehicles and other light armored vehicles, as well as armored protection for armed helicopter webs and ship superstructures.
⑵ In the field of nuclear industry:
Boron carbide can absorb a large number of neutrons without forming any radioactive isotopes, so it is an ideal neutron absorber in nuclear power plants, and neutron absorbers mainly control the rate of nuclear weapons. Boron carbide is mainly made into a controllable rod shape in the nuclear reactor field, but sometimes it is made into a powder because of the increase in surface area.
During the Chernobyl nuclear accident in 1986, *** dropped nearly 2,000 tons of boron carbide and sand, which eventually stopped the chain reaction in the reactor. It can be used to manufacture gun nozzles in the military industry. Boron carbide, extremely hard and wear-resistant, does not react with acid and alkali, resistant to high/low temperature, high pressure, density ≥2.46g/cm3; microhardness ≥3500kgf/mm2, bending strength ≥400Mpa, melting point 2450℃. .Boron carbide is used to make control rods, regulating rods, accident rods, safety rods, and shielding rods for nuclear reactors, and to make boron carbide tiles, plates or neutron absorbers (made of high B10 content powder) for radiation protection, or the same Cement mixed to make nuclear reactor shielding layer is an important functional component second only to nuclear fuel components. Features: Boron carbide can absorb a large number of neutrons without forming any radioactive isotopes, so it is an ideal neutron absorber in nuclear power plants and is also a nuclear reactor core component. The neutron absorber is mainly to control the rate of nuclear weapons, but to increase the surface area, it is made into powder. Boron carbide has high neutron absorption cross-section, wide absorption energy spectrum, low price, rich source of raw materials, there is no strong secondary radiation of lambda ray after absorbing neutrons, so the waste is easy to handle, so boron carbide is an important neutron absorption material.
⑶ In the field of refractory materials:
Boron carbide is used as an antioxidant additive for low-carbon magnesia carbon bricks and castables. It is used in key parts of high temperature resistance and erosion resistance in the steel industry. Such as ladle, tap (nozzle), skateboard, stopper, etc. With the need for energy saving and consumption reduction in the iron and steel industry and the need for smelting low-carbon steel and carbon steel, the research and development of low-carbon magnesia-carbon bricks with excellent performance (general carbon content <8%) has attracted increasing attention from domestic and foreign industries. At present, the use of low-carbon magnesia-carbon bricks is generally improved by improving the bonded carbon structure, optimizing the matrix structure of magnesia-carbon bricks, and adding high-efficiency antioxidants. Among them, graphitized carbon black composed of industrial grade B4C and partial graphitized carbon black is used. Composite powder, using it as a carbon source and antioxidant for low-carbon magnesia-carbon bricks, has achieved good results. Low-carbon magnesia-carbon bricks added with B4C have good conventional physical properties, oxidation resistance and thermal shock stability.
Features: Boron carbide has an anti-oxidation effect in carbon-containing refractories, which can densify the product and prevent the oxidation of carbon in carbon-containing refractories. At the same time, it will react at 1000°C~1250°C to form (9AL2O3•2B2O3) columnar crystals distributed in the refractory In the matrix and gaps, the porosity is reduced, the medium temperature strength is improved, and the volume expansion of the generated crystals can heal volume shrinkage and reduce cracks
⑷Used for other engineering ceramic materials:
Boron carbide makes nozzles for sandblasting machines, nozzles for high-pressure water cutting machines, sealing rings, pottery molds, etc. Features: Boron carbide nozzles have the characteristics of wear resistance and high hardness, which will gradually replace the known sandblasting nozzles of cemented carbide (tungsten steel) and silicon carbide, silicon nitride, alumina, zirconia and other materials. In addition, the application of boron carbide in the field of composite ceramics: boron carbide is a compound with strong covalent bonds, and the plasticity of boron carbide is very poor, and the resistance of the grain boundary is very large. It is difficult to obtain a dense sintered body, except for some special In occasions, such as microcrystalline boron carbide gas dynamic bearing materials and boron carbide blocks used as neutron absorbing materials in atomic energy reactors, sintering aids are usually used to improve the sintering behavior of boron carbide and obtain cheaper , Practical boron carbide products. What is more noteworthy is that B4C-SiC composite ceramics can better maintain the excellent physical and mechanical properties of boron carbide ceramics while reducing the sintering conditions of boron carbide ceramics. B4C-SiC ceramics are considered to be a kind of high-temperature, corrosion-resistant and wear-resistant materials with broad application prospects, and have been applied in the fields of industrial nozzles, pump seals, and hot extrusion dies.
In recent decades, due to the rapid development of science and technology, especially the rapid development of electronic technology, space technology, and computer technology, materials with special properties are urgently needed. Boron carbide has become an important member of the *** ceramic family because of its many excellent properties. At present, many problems related to the preparation of boron carbide powder and the sintering of boron carbide ceramic materials have been solved. In the future material field, boron carbide will certainly occupy an important position with its excellent performance. Figure 7
(5) In general industrial fields:
Boron carbide is used to make high-grade wear-resistant electrodes to enhance the wear-resistant strength of the welding surface; used as grinding and polishing materials, abrasives for water cutting and diamond abrasive correction materials; high-precision polishing and grinding in the jewelry industry. Characteristics: Boron carbide is a solid harder than silicon carbide or tungsten carbide. It was used as a coarse abrasive material a long time ago. Because of its high melting point, it is not easy to cast finished products, but by smelting the powder at high temperature, it can be processed into simple shapes for grinding, grinding, drilling and polishing of cemented carbide, gems, etc.
(6) Application of electrical properties of boron carbide:
The boron carbide-graphite thermocouple consists of a graphite tube, a boron carbide rod and a boron nitride bushing between the two. In inert gas and vacuum, the operating temperature is as high as 2200℃. Between 600~2200℃, the potential difference has a good linear relationship with temperature.
(7) Application of boron carbide as chemical raw material:
Boron carbide powder is activated by halogen and can be used as a boronizing agent for steel and other alloys to boron on the surface of steel to generate a thin layer of iron boride to enhance the strength and wear resistance of the material. Boron carbide can also be used as a non-metallic additive for some metal-based friction materials. In the reduction-chemical method to prepare boride powder, boron carbide is used as a boron source to obtain TiB2, ZrB2, CrB2 and other powders, which is called the "boron carbide method" for preparing powders.
(8) Application of boron carbide in sapphire wafer (LED):
In recent years, the country's strong support and promotion of the LED industry has made the development of the LED industry better, which has brought great business opportunities to enterprises that produce and process sapphire crystals. Due to the high strength and hardness of sapphire crystals (Mohs hardness 9), it brings great difficulties to processing enterprises. From the perspective of materials and grinding science, the materials used for processing and grinding sapphire crystals are synthetic diamond, boron carbide, and silicon dioxide. Because the artificial diamond is too hard (Mohs hardness 10), it will scratch the surface when grinding the sapphire wafer, which will affect the light transmittance of the wafer, and it is expensive. Insufficient silica hardness (Mohs hardness 7) and poor grinding force are time-consuming and labor-intensive in the grinding process. Therefore, boron carbide abrasive (Mohs hardness 9.3) becomes the most ideal material for processing and grinding sapphire crystals. Boron carbide abrasives have excellent performance in double-sided grinding of sapphire wafers and back thinning and polishing of sapphire-based LED epitaxial wafers. Some key national universities also have major researches on the grinding of sapphire crystals with boron carbide. In short, with the rapid development of the LED industry, boron carbide will also rise rapidly.
In short, with the development of society and technology, the application fields of boron carbide will be continuously discovered and expanded, and the market application prospects will be broader.