Advanced Ceramic Materials

Silicon carbide is a synthetic carbide with a molecular formula of SiC. It is usually formed by silicon dioxide and carbon at a high temperature of 2000°C or higher after electrification. Due to its high hardness, high wear resistance, high corrosion resistance and high-temperature strength, SiC is used in various wear-resistant, corrosion-resistant and high-temperature resistant mechanical parts. Chemical properties Oxidation resistance: When silicon carbide is heated to 1300°C in air, a protective layer of silicon dioxide begins to form on its crystal surface. With the thickening of the protective layer, the internal silicon carbide is prevented from being oxidized, which makes the silicon carbide have better oxidation resistance. However, when the temperature reaches 1900K (1627°C) or higher, the silicon dioxide protective film begins to disappear, and the oxidation of silicon carbide intensifies.　　 Acid and alkali resistance: due to the silicon dioxide protective film on its surfa

Bearing Material Selection The choice of bearing material is essential for its reliable operation. For many years, materials such as rubber, bronze and ceramics have been used to make bearings. Different materials have different effects. Among them, ceramics and graphite are widely used in bearing manufacturing. Silicon Carbide Bearing There are many types of ceramic materials including oxides, borides, and nitrides. The typical ceramic material used for bearing manufacturing and achieving good performance is silicon carbide. Silicon carbide is sintered at high temperature in a resistance furnace using quartz sand, petroleum coke and other raw materials. It is a hexagonal crystal with a relative density of 3.20 to 3.25 g / cm3 and a micro hardness of 2 840 to 3320 kg / mm2. Silicon carbide has the advantages of high hardness, good wear resistance, corrosion resistance, oxidation resistance, and low temperature creep. It has been widely used as a wear part in many fields.

Hexagonal boron nitride is a white powder with good lubrication properties, high temperature resistance, corrosion resistance, high thermal conductivity, and good insulation properties. HBN is called white graphite because it has a similar layered crystal structure and physical and chemical properties similar to graphite (good lubricity and thermal conductivity). It is commonly used as a sintered ceramic material. In addition, due to its high thermal conductivity, good electrical insulation properties, low thermal expansion coefficient and non-thermal properties, h-BN structural ceramics have been widely used in high temperature insulation components, atomic energy, metallurgy, aviation and other fields. As a raw material for synthesizing cubic boron nitride, hexagonal boron nitride is a theoretical low-temperature stable phase, and its excellent performance is more attractive. Therefore, hexagonal boron nitride is commonly used to synthesize cubic boron nitride. Hexagonal boron

Graphene has been fascinating to scientists since its discovery more than a decade ago. This carbon material with only one atomic thickness has excellent electronic properties, strength and ultra-lightweight. Its use is also expanding, but how to implant the energy gap (bandgap/semiconductor or insulator valence band tip to the energy gap at the bottom of the conduction band) to make transistors and other electronic devices, but always let the researchers do nothing. Graphene  Researchers at the Massachusetts Institute of Technology (MIT) have made major breakthroughs in this area and are even expected to change some of the theoretical predictions of graphene physics. They introduced another material with single atomic thickness and properties similar to graphene: hexagonal boron nitride (HBN) . They placed a layer of graphene on the HBN, and the resulting hybrid material had both the conductive properties of graphene and finally the energy gap necessary to build the transistor.

The  boron nitride rods are made of boron nitride ceramics and are processed through the following series of steps: forming, grouting, grouting, drying, extrusion, cold, static pressure, hot pressing, hot isostatic pressing. They have excellent resistance to falling, abrasion, super strong, super hard, high temperature (refractory), super corrosion resistance, never rust, oxidation resistance and insulation performance. The reasonable combination of bending strength and elasticity gives the ceramic rods a high impact strength. Boron nitride ceramic rods are easy to maintain and require no paint or protective finish on the surface and cutting edges. Different shapes, sizes and precision products require different forming methods during the molding of boron nitride ceramic rods. Injection Molding Process: purchase airflow powder  →  with chemical components  →  stir evenly  →  dry  →  break  →  injection molding →  Discharge  →  Sintering  →  Post-processing Inject

At present, the most striking preparation method of zirconia ceramics is ultra-high temperature technology. This technology is inexpensive for zirconia ceramic preparing, as well as the preparation of new glass materials, such as optical fiber, magnetic glass, hybrid integrated circuit board, zero-expansion crystallized glass, high-strength glass, artificial bone and tooth stick. In addition, ultra-high temperature technology can also be used to develop materials such as tantalum, molybdenum, tungsten, vanadium-iron alloy and titanium that can be used in space flight, ocean, nuclear fusion and other fields. The zirconia ceramic ultra-high temperature technology has the following advantages: it can produce substances that cannot be produced by conventional methods; it can obtain substances with extremely high purity: productivity can be greatly improved; and the operation procedure can be simplified and easy. In addition to ultra-high temperature technology, preparation of

Lanthanum hexaboride LaB6 cathode material: Lanthanum hexaboride has the characteristics of high emission current density and low evaporation rate at high temperature. Therefore, as a cathode material, it has gradually replaced some tungsten cathodes in industrial applications. At present, the main application fields of lanthanum hexaboride LaB6 cathode materials are as follows: 1 Microwave vacuum electronic devices and ion thrusters in the fields of military and space technology, and new technology industries such as display and imaging devices and electron beam lasers with high definition and high current emissivity required by civil and military industries. In these high-tech industries, the demand for low temperature, high uniform emission, high current emission density and high lifetime cathode materials has been very tight. 2 Electron beam welding industry. For electron beam welders, electron beam melting and cutting equipment. The cathode material should meet the re