碳化硅的特性和应用

Silicon carbide, better known by its acronym SiC, is one of the hardest synthetic materials on the market today and widely utilized for use in cutting tools due to its hardness, as well as refractories due to its resistance against high heat and thermal shock. It has also found widespread application as an anticorrosive coating material in electronics applications.

SiC is an extremely durable hexagonal chemical compound with wide band-gap semiconductor properties. This allows SiC to withstand higher electric fields while operating at faster speeds.

Conductivity

Silicon carbide in its pure form acts like an electrical insulator; however, by adding impurities or dopants (dopants are used to add dopants that change its electrical conductivity), its behavior changes to become semiconductive and eventually semiconductive again. With doping by elements like aluminum, boron, gallium or nitrogen/phosphorus respectively (p-type or n-type semiconductor respectively).

Silicon carbide’s crystalline structure comprises of two primary coordination tetrahedra composed of four silicon and four carbon atoms bonded together, creating strong electrostatic interactions which repel protons, electrons and neutrons from its surfaces – thus rendering it resistant to corrosion by many chemical agents such as acids.

Repelling charge carriers also increases its thermal conductivity, making the material extremely heat resistant and suitable for operating at higher temperatures. Because it so effectively resists charge carriers, ceramic can even be used in bulletproof vests where bullets cannot penetrate through its hard ceramic blocks structure.

SiC has a wider bandgap than standard silicon semiconductors, meaning it can accommodate higher voltages and frequencies while handling greater power loads – an important characteristic for electronics that require handling more power at higher voltages and frequencies, such as electric vehicles and spacecraft power electronics components.

耐用性

Silicon carbide’s durability, hardness and corrosion-resistance make it an excellent material for high-performance engineering applications such as pumps bearings, valves, sandblasting injectors or extrusion dies. Furthermore, its strength, chemical inertness and low thermal expansion make it suitable for extreme and high-temperature engineering applications.

Silicon carbide, more commonly referred to as “carborundum,” is produced through the combination of silicon and carbon to form a strong ceramic with hexagonal structures. Due to its wide band gap semiconductor properties, silicon carbide can withstand voltages 10 times greater than that of silicon.

SiC is found naturally in moissanite, which was first discovered at Arizona’s Canyon Diablo meteor crater in 1893. More often though, this material is produced synthetically as gem and abrasive grades; typically in electrical resistance furnaces operating at temperatures ranging between 1700-2500degC.

Elkem Processing Services (EPS), located in Liege, Belgium, uses reactive sintering to produce silicon carbide to the exact specifications of customers worldwide. This facility boasts the latest technological capabilities to produce large volumes of SiC quickly – as well as creating custom blends tailored specifically for other uses.

耐腐蚀性

Silicon carbide is an extremely hard and wear-resistant material. It retains its strength under high temperatures, making it suitable for applications requiring significant thermal shock resistance. Furthermore, its corrosion-resistance makes it suitable for most acids, alkalis and molten salt solutions.

American inventor Edward Acheson discovered silicon carbide in 1891 while searching for ways to produce artificial diamonds. In order to do so, he heated clay mixed with powdered coke using an ordinary carbon arc light and spark plug, producing bright green crystals with hardness close to that of diamond that became known later as carborundum (SiC).

Modern manufacturing methods used by abrasives, metallurgical, and refractory industries use similar processes as those developed by Acheson. Raw materials like pure silica sand and finely ground carbon in coke form are placed around a carbon conductor inside a brick electrical resistance-type furnace with an electric current passed through it; this causes chemical reaction between carbon in the coke and silicon in the sand, producing SiC.

Silicon carbide possesses many desirable characteristics and is frequently combined with other metals to form metal matrix composites (MMCs). MMCs combine the strength and durability of SiC with conductivity from other metals. Furthermore, MMCs are highly resistant to erosion-corrosion and oxide spallation damage.

实力

Silicon carbide, commonly referred to as “carborundum,” boasts an incredible Mohs hardness rating of 9, making it harder than diamond and boron carbide. Due to its strength and durability, silicon carbide makes an excellent material choice for applications ranging from abrasives to bulletproof vests – it possesses superior abrasion resistance while still maintaining its hardness even at very high temperatures; in fact, silicon carbide stands as one of the hardest advanced ceramics.

Silicon Carbide is a semiconductor material, meaning that electric currents or electromagnetic fields can alter its conductivity to alter its conductivity, making it useful in electronic devices that amplify, switch or convert signals in an electrical circuit. Silicon carbide semiconductors have greater electron mobility and lower power loss compared to their silicon counterparts – making them perfect for high-speed transistors, diodes and FETs.

Modern silicon carbide production for use in the abrasives, metallurgical, and refractory industries resembles Acheson’s process: A mixture of pure silica sand mixed with finely ground coke carbon is assembled around an electric furnace carbon conductor; electricity passes through this conductor to promote chemical reaction between silicon and carbon that yields both silicon carbide and carbon monoxide gas production; finally the granular silicon carbide is ground to its desired size and density using special equipment.