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Silicon carbide (SiC) is an exceptionally hard, heat-resistant ceramic that features many desirable characteristics, making it suitable for high performance applications that demand strong materials with heat tolerance. SiC is often chosen over traditional ceramic options for this reason.

American Elements offers SiC in numerous grades for military, ACS and reagent use; food grade pharmaceutical research applications as well as abrasive products.

Tvrdost

Silicon carbide (SiC) is an impressive performance material with many exceptional physical-chemical properties, including high hardness and mechanical stability at elevated temperatures, exceptional thermal conductivity with a low coefficient of expansion, strong corrosion and oxidation resistance and its composition of tetrahedral structures composed of silicon and carbon held together by strong covalent bonds in its crystal structure. These impressive characteristics come together in SiC’s striking physical-chemical profile.

In 1891, American inventor Edward G. Acheson discovered silicon carbide while trying to produce artificial diamonds. To do this, he heated a mixture of clay and powdered coke in an iron bowl using its electrode and an ordinary carbon arc light as electrodes; upon seeing bright green crystals attached to one electrode he knew he had made an important discovery and called his new compound “carborundum,” with hardness similar to diamond.

Silicon carbide’s high melting point, chemical inertia and thermal shock resistance make it suitable for harsh industrial environments with extreme temperature extremes such as high-temperature molten metals and petrochemical furnaces. Furthermore, its strength, durability and corrosion resistance make it useful in engineering applications such as sand blasting injectors, pump bearings and cutting tools.

SiC can be produced either through sintering pure silicon and carbon powder or reaction bonding; its formation method greatly affects its final microstructure. Reaction bonded SiC is formed by infiltrating mixtures of SiC with liquid silicon; these infiltrated compacts react with carbon to bond to their original particles, creating reaction bonds between SiC particles. Sintered SiC is prepared by mixing pure SiC powder with non-oxide sintering aids before using conventional ceramic forming processes to sinter the material at high temperatures.

Utilizing an appropriate hardness testing system, hardness can be measured on samples from all types of materials. To create correlations between hardness and other properties such as tensile strength, hardness test results must first be calibrated against those used for calibration.

According to different types of indenters, loads, and dwell times, hardness testing of materials may vary widely. Therefore, hardness tests should only be used as a rough guide when screening materials intended for critical applications.

Odolnost proti korozi

Silicon carbide is a nonoxide ceramic with excellent corrosion resistance in harsh industrial environments. The material’s crystalline structure prevents direct contact between oxygen molecules and its surface layer, helping it avoid decay over time. This feature makes silicon carbide especially valuable in high-temperature applications where aggressive chemical agents such as molten salts or metal alloys could potentially attack it, making its high temperature resistance a key benefit of using silicon carbide for refractories, ceramics and glass industries.

Sintered silicon carbide (SSiC) stands out for its corrosion resistance, with this material having the ability to withstand an impressive variety of acids (phosphoric, sulfuric, hydrochloric and nitric acids) as well as bases like amines potash and caustic soda. Furthermore, it features low thermal expansion rates and can even serve as an ideal refractory in high-temperature applications; it is also commonly used as wear-resistant material in pumps valves sandblasting injectors and extrusion dies.

Sand-blasted SiC is frequently utilized in carborundum printmaking, which uses ceramic plates with granular surfaces that trap ink from rollers to produce printed marks on paper. Furthermore, silicon carbide has long been utilized as an impact absorbent component in bulletproof vests due to its ability to mitigate high-velocity impacts.

Modern manufacturing of silicon carbide-based abrasives, refractories and ceramics utilizes a mixture of pure silica sand mixed with carbon coke that is placed around a carbon conductor within an electrical resistance-type furnace, where electric current causes chemical reactions between carbon in the coke and silicon in the sand which leads to product sintering at elevated temperatures.

Junty offers a comprehensive selection of SiC products tailored to meet your exacting specifications, such as sand-blasted granules, sintered spherical grains, pressed spherical pieces and graphite-loaded silicon carbide refractories. Each type is available in multiple sizes to accommodate various applications – reach out today and see how we can enhance the performance of your application by providing quality materials meeting or exceeding industry standards in an expedient and on budget fashion!

Elektrické vlastnosti

Silicon carbide possesses the unique property of acting both like a metal and an insulator at low temperatures, but also as a semiconductor at higher temperatures, allowing current to pass freely through.

SiC is an ideal material for electrical applications at higher voltages, especially due to its increased conductivity. SiC’s reduced system loss and energy consumption make power electronics devices smaller and more energy-efficient – this also aids fast charging systems for electric vehicles by speeding up charge times while decreasing overall system size and weight.

Sintered silicon carbide production starts with a mixture of carbon material and raw materials like petroleum coke or quartz sand being chemically reacted at extremely high temperatures in an electrically resistive furnace to form SiC. Once formed, this crude material must then be processed through crushing and milling to achieve the required size and shape of grain before further sorting and chemical treatment to obtain purity levels suitable for particular applications.

Temperature and impurity content determines which forms of SiC are produced; for instance, alpha silicon carbide (a-SiC), featuring hexagonal crystal structure and wurtzite (ZnCr2O4) formation occurs at higher temperatures while beta SiC (ZnSiC) forms at lower temperatures.

Silicon carbide stands out not only with its electrical properties, but also for its chemical inertness at higher temperatures – something which makes it an attractive candidate for ceramic applications such as automotive brakes and clutches, bulletproof vests and bullet-resistant vests. High-grade SiC can withstand the high stresses and temperatures encountered during these applications, providing longer lifespan and increased performance. Silicon carbide transistors also possess a much higher breakdown voltage compared to their silicon counterparts, reducing power losses and increasing efficiency. Silicon carbide’s electrical insulation properties make it particularly advantageous for electric vehicle chargers, which must withstand large voltages without experiencing unpredictable conduction behavior or catastrophic failure. Therefore, many EV manufacturers are turning to silicon carbide in their products.

Chemical Inertia

Silicon Carbide (SiC) is an extremely hard chemical compound of silicon and carbon that occurs naturally as the rare mineral moissanite; however, since 1893 mass production has made this chemical material available as powder or crystal for abrasives use. Grain of silicon carbide can also be bonded together into ceramic materials used in car brakes, clutches, bulletproof vest plates, as well as in bulletproof vest liners. Finally large single crystals of SiC may also be created through sintering to produce synthetic moissanite gemstones known as synthetic moissanite.

Silicon carbide’s combination of high temperature strength, low thermal expansion and resistance to corrosion makes it suitable for a range of industries. Boasting a Mohs hardness rating of nine – second only to diamond and boron carbide – silicon carbide makes a highly sought after material in abrasives such as grinding wheels or paper and cloth products as well as chemical resistant refractories production.

Ceramic material offers excellent resistance against acids and alkalis, molten metals and glass attacks as well as thermal shock. Furthermore, its zero porosity and low pore density makes it suitable for mechanical seals and bearings that must operate under aggressive environments with little lubrication required.

Silicon carbide’s high temperature strength, stiffness and rigidity make it a desirable material for use in mirror construction for astronomical telescopes. While this application of this versatile material may still be relatively novel, several observatories like Herschel Space Telescope already employ silicon carbide mirrors in this capacity. Furthermore, silicon carbide’s low thermal expansion offers advantages when used to construct kiln linings and furnace walls as well as for ceramic products like sanitaryware.

Zirconia-based SiC electrolyte materials are currently undergoing research as potential ways of improving battery technology. While they offer good ionic conductivity and structural integrity, the preparation process requires high operating temperatures for optimal results. While cost prevents widespread adoption, Zirconia IGBTs offer advantages over silicon IGBTs for power conversion applications exceeding 600V.