Sexual energy
Mechanical property
Ceramic material is the best stiffness and highest hardness of engineering materials, and its hardness is mostly above 1100HV. The compressive strength of ceramics is high, but the tensile strength is low, and the plasticity and toughness are poor.
Thermal characteristic
Ceramic materials generally have a high melting point (mostly above 1500℃), and have excellent chemical stability at high temperatures; The thermal conductivity of ceramics is lower than that of metal materials, and ceramics are also good high-temperature resistant materials. At the same time, the coefficient of linear expansion of ceramics is lower than that of metals, and the ceramics have good dimensional stability when the temperature changes.
Electrical characteristic
Most ceramics have good electrical insulation, so they are widely used to make insulating devices with various voltages (1kV~110kV). Ferroelectric ceramics (barium titanate BaTiO3) has a high dielectric constant, can be used to make capacitors, ferroelectric ceramics under the action of external electric fields, can also change the shape, the electrical energy into mechanical energy (with the characteristics of piezoelectric materials), can be used as a power amplifier, record player, ultrasonic meter, sonar, medical spectrometer, etc. A few ceramics also have the characteristics of semiconductors and can be used as rectifiers.
Chemical characteristic
Ceramic materials are not easy to oxidize at high temperatures, and have good corrosion resistance to acids, alkalis and salts.
Optical characteristic
Ceramic materials also have unique optical properties, which can be used as solid laser materials, optical fiber materials, optical storage, etc. Transparent ceramics can be used for high-pressure sodium lamp tubes. Magnetic ceramics (ferrites such as MgFe2O4, CuFe2O4, Fe3O4) have a wide range of applications in recording tape, record, transformer core, large computer memory components.
1. Alumina - cost-effective (pottery)
Pottery is a kind of porous and opaque ceramic. Unlike vitrified translucent porcelain, it needs to be glazed to hold the liquid. Although it is not particularly hard, less dense than porcelain and porcelain clay, and more prone to fragmentation, the advantages of clay are that it is not easily deformed in low temperature burning, and high stability in production and processing.
Material characteristics: general sintering temperature below 1200 degrees Celsius; The deformation during baking is smaller than that of porcelain. A variety of processing technology; Low cost; More fragile than China.
Typical use: Materials for a wide range of applications, from large sanitary ware to cup and saucer products.
2. Zirconia - wear resistance
Zirconia is another high performance ceramic material. The reason why the use of zirconia is more than alumina, because its tough characteristics make it more resistant to cracking, zirconia particles are smaller, which makes the surface of the product made of it more rounded, but also makes it suitable for the production of tools, pistons, bearing products, and even gorgeous jewelry products.
Ultrafine zirconia or titanium carbide powder can be used in the production of watches. The powder is pressed and then sintered at 1450 degrees Celsius and polished with diamond sand to make its surface brighter and more metallic.
Material properties: excellent strength and fracture toughness; Super hard, super wear resistance; Excellent chemical stability; High temperature resistance; Dense; Low thermal conductivity (20% of alumina)
Typical use: After these advanced ceramic materials are used in watches, its smooth surface and toughness make zirconia the perfect ceramic raw material for making cutting props and kitchen knives.
3. Silicon nitride - strong pressure resistance
Silicon nitride is one of the three hardest materials in the world. Its hardness is second only to diamond and cubic boron nitride. Silicon nitride was discovered in the 1960s by a group of engineers looking for materials that could withstand the harsh operating environments inside jet engines.
Ceramics are very hard, with excellent wear loss properties and compression properties, and silicon nitride is one of the most characteristic materials in ceramics, it is dark gray or black, polished with a mirror-like surface. Science fiction writers in the '50s fantasized about flying cups made of silicon nitride.
Material characteristics: friction is 80% lower than steel; Three times harder than steel; 60% lighter than steel; Operating temperature lower than steel.
Typical use: Often used in the main engine of the space shuttle, military missiles, gyroscopes. The superhardness of silicon nitride makes it the main material for bearings in products such as Marine fish reels, bicycle racing cars, ice skates, skate boards and so on.
4. Quartz material
Quartz is a versatile material, its optical applications include piezoelectric bodies and watches, quartz also has excellent physical properties and decorative. As one of the most resource-rich minerals in the world, its good hardness and beauty make it a material for making workbench surfaces, which is one of its main uses.
Material characteristics: high hardness; Good color consistency; Without pore; Excellent durability; Heat resistant; stain-resistant
Typical use: A large number of appearance materials used in commercial and household products. Commercial applications include wall interlayers, work surfaces, front tables, bar tables, laboratory tables, kitchen tables and shower enclosures.
5. Boron nitride
Although the amount of boron nitride in cosmetics is not much, usually only 3% to 10% of boron is added in cosmetics, but these ingredients can better adhere to the skin, so that the skin looks more delicate and lubricated.
Different grades of boron nitride are used in a large number of very different products. Like diamond and silicon nitride, cubic boron nitride crystals are among the hardest materials in the world, making them excellent materials for cutting tools.
Boron nitride is divided into two types: one is hexagonal boron nitride with high temperature resistance similar to graphite, known for its smooth and soft characteristics; The other is cubic boron nitride, which has excellent hardness and is commonly used for cutting, grinding and drilling.
Material characteristics: silky smooth; Excellent adhesion; There are various levels of products, can be widely used in a large number of products; Inconvertibility; Good lubricity; Chemically inactive; non-toxic
Typical use: High purity boron nitride powder can be used in cosmetics such as foundation cream, lipstick, eyebrow pencil and so on. Its good lubrication characteristics enable it to minimize friction in many raw materials and industrial production processes.