Advanced Ceramic Materials

Fuel cells are new energy technologies with broad application prospects. Carbon-supported platinum-based catalysts (Pt/C) are the most commonly used fuel cell electrode catalysts, but the poor stability and high cost of Pt/C severely limit their large-scale applications.  Covalent carbides, silicon carbide , and boron carbide , have excellent physicochemical stability due to their extremely strong covalent bonds, and have become important basic materials for the preparation of fuel cell catalysts with high stability and low cost. Hydrogen is widely used in many fields such as industry and medical treatment, and it is also one of the most commonly used fuels for fuel cell anodes. Platinum-based catalysts are still the best hydrogen production catalysts. Silicon carbide (SiC) is a compound with very stable physicochemical properties. Composite nanomaterials with SiC as an important component are also often used as supports for platinum-based catalysts. B4C is a highly stable covalent

  Silicon Carbide Tube Overview Silicon carbide tube has the advantages of high strength, high hardness, good wear resistance, high temperature resistance, corrosion resistance, good thermal shock resistance, high thermal conductivity and good oxidation resistance. Silicon carbide tubes are mainly used in intermediate frequency casting, various heat treatment electric furnaces, metallurgy, chemical industry, non-ferrous metal refining and other industries; siliconcarbide protection tubes are widely used in metallurgical sintering furnaces and intermediate frequency heating casting furnaces, and the length can be customized according to the actual needs of the applications. Characteristics of Silicon Carbide Tubes Silicon carbide tube is a high-quality product fired at high temperature with silicon carbide as theprimary raw material . It has high temperature resistance, corrosion resistance, fast thermal conductivity, high strength, high hardness, good wear resistance, and good th

Little radiation Medical zirconia is cleaned and processed, leaving a small amount of alpha ray residue in zirconium, which penetrates to a small depth of only 60 microns. High density, high strength, metal-free inner crown Zirconia has unique resistance to cracking and strong curing performance after cracking. It can be used to make more than 6 units of ceramic bridges. Although there is no metal support, it has high strength, and its refractive index is basically close to that of natural teeth, with dense edges and high precision, and has excellent aesthetic effects: Zirconia ceramics are usually yttrium-stabilized zirconia ceramics with high flexural strength. Compared with other all-ceramic restoration materials, the strength advantage of zirconium dioxide material allows doctors not to rub the patient's real teeth too much. Excellent aesthetic effect Zirconia all-ceramic teeth have a realistic and beautiful appearance, solid and wear-resistant, similar in color

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.