Silicon carbide is an outstanding ceramic with superior mechanical properties. It features superior hardness and density compared to popular ceramics such as alumina or boron carbide.
Hexoloy(r) SiC is a pressure-less sintered beta silicon carbide used for multiple applications. Our application engineers can assist in designing solutions to address even your toughest challenges.
Tvrdost
Silicon carbide is one of the hardest synthetic materials produced, boasting a Mohs hardness rating of 9. This extreme hardness makes silicon carbide ideal for grinding wheels, abrasive paper and cloth products, refractory linings in industrial furnaces and cutting tools; plus its low thermal expansion rate and resistance to chemical attacks makes it suitable as wear-resistant parts in seal rings or pumps.
Silicon carbide comes in various forms and grades that each serve specific uses. Black silicon carbide (known as a-SiC or b-SiC) features superior toughness than its green counterpart and is often used for processing glass, ceramics, stone and refractory materials. Furthermore, this form is great for high temperature mechanical applications as its creep resistance ensures strength up to 1600degC.
Silicon carbide’s combination of high hardness, rigidity, and thermal conductivity make it an excellent material choice for mirrors in astronomical telescopes. Chemical vapor deposition has become more efficient over the past several years to produce disks of polycrystalline silicon carbide with diameters reaching up to 3.5 meters (11.5 feet), with several telescopes such as Herschel Space Telescope featuring sic optics. Furthermore, silicon carbide’s low thermal expansion coefficient makes it suitable for spacecraft subsystems as it will not expand or contract in response to higher temperatures.
Beta silicon carbide shares many similarities with alpha silicon carbide, though its denser structure makes it distinct in both physical and electrical applications. Commercial use has been somewhat limited compared to that of alpha SiC; however it can still play a critical role in certain refractories and sawing applications due to its cubic microstructure that allows electrons to pass more freely along its surfaces than it does for its alpha counterpart.
Superior Graphite offers Sinter-Pur Beta sintered beta silicon carbide material as a highly efficient sliding contact material, ideal for applications such as mechanical seal faces in pumps and spray and blasting nozzles, as well as high abrasion/erosion resistant applications such as bearing surfaces in product lubricated bearings.
Temperature Resistance
Silicon carbide stands out among materials in terms of its high temperature resistance. This property makes silicon carbide ideal for resisting the intense heat produced by electrical devices like semiconductors and transistors, providing superior thermal conductivity with minimal expansion at higher temperatures. Thanks to this unique combination of properties, silicon carbide has become a vital component in advanced electronics such as computers and cell phones as well as various refractory applications like bulletproof vest plates or ceramic knives.
Researchers conducted numerous experiments to measure the temperature resistance of sintered alpha silicon carbide. They exposed porous particles of a-type crystal silicon carbide spheroidal shape spherically coated in pure hydrogen at temperatures between 1000 and 1400 C and discovered that they could withstand such temperatures without losing their original spherical form, but found that during sintering this porosity of material had been compromised significantly.
Sintering processes were conducted at various temperatures, each leading to an increase in density for the material produced. Results demonstrated that particle size played a vital role in determining final density levels; furthermore, sintering had an impact on fracture toughness – an outcome which may help prolong durability of silicon carbide heating elements commonly found in household appliances.
Researchers conducted their experiment using commercially available alpha-SiC powder that contained boron and carbon as sintering aids, and could be sintered between 1900 C to 2150 C for 30 minutes under one atmosphere of argon pressure. Sintering process was successful, producing material with an overall density exceeding 96% of theoretical value. Accordingly, research suggests this can be used for producing alpha silicon carbide components with high strength and low porosity. This research also shows how alpha-SiC powder can be combined with various polymers to increase its mechanical properties, such as hardness and temperature resistance. Furthermore, using the sintering method produced polymer-coated sintered alpha-SiC which could then be utilized in composite materials with increased levels of strength for use in applications that demand increased strength.
Tepelná vodivost
Thermal conductivity values for alpha silicon carbide vary significantly depending on its preparation method; for instance, sintering often produces lower values while high-pressure injection molding has shown to produce greater ones. Furthermore, polycrystalline structure also affects property values with alpha variety (a-SiC) being much lower in comparison to beta variety (b-SiC) produced at temperatures under this threshold temperature.
Thermal conductivity variations arise largely from differences between the crystal structures of two SiC polymorphs; specifically a-SiC has an hexagonal crystal structure similar to Wurtzite while beta variety features a zinc blende structure more comparable with diamond. This contrast manifests itself through high hardness in a-SiC but lower thermal conductivity for b-SiC.
A-SiC boasts superior chemical stability and high temperature resistance, along with good electrical and electronic conductivity, making it an excellent raw material for manufacturing ceramics. Furthermore, a-SiC serves as the cornerstone ingredient in refractory material products like bricks and coatings.
Addition of a-SiC to an alloy can significantly enhance its properties. The particles of a-SiC increase hardness, thermal conductivity, coefficient of expansion reduction and Young’s modulus increases, as well as corrosion and wear resistance of the alloy.
A-SiC can be used to produce high-performance ceramic products such as ceramic knives and insulators; also used in cutting/grinding tools; also found widely used as an electric heating element and other refractory products.
Hexoloy SP SiC is a sintered alpha silicon carbide material designed to provide superior sliding contact performance in applications such as mechanical seal faces and product lubricated bearings. Hexoloy SP SiC’s superior friction properties come from its presence of spherical pores which serve as fluid reservoirs to keep a film of lubrication between sliding components intact.
Self-Sharpness
Alpha silicon carbide powder stands out from other abrasives by being self-sharp and maintaining its cutting edge, making it suitable for grinding hard yet low tensile strength materials such as chilled iron, marble, rubber leather and copper – as well as those that require sharp cutting actions such as rubber leather and copper. Furthermore, its chemical inertness and good electrical properties make it suitable for use with electrical heating elements.
Alpha silicon carbide’s dense density and self-sharpening characteristics make it an excellent material for heavy grinding applications, from car brakes and clutches to bulletproof vest ceramic plates. Furthermore, alpha silicon carbide is often used to craft hard cutting tools capable of cutting through steel or other metals.
Alpha silicon carbide can be manufactured into complex bonded shapes or used as loose abrasive grains, powders or compounds. It comes in different grades depending on its purity, polycrystalline type and method of formation; below 1800 degC it forms into spherical varieties while above this temperature it develops either rhombohedral or hexagonal structures.
beta silicon carbide has many uses outside the abrasives industry, such as non-metallic refractories, electrical components and ceramics. It is often combined with other non-metallic refractories to form ceramic armors used by oil and gas industries to protect equipment against impacts; additionally it is utilized in producing seals, nozzles, sintered wear parts and specialty filters.
Silicon carbide, also known as carborundum, is an inorganic chemical compound composed of silicon and carbon that occurs naturally as the rare mineral moissanite; since 1893 however it has been mass produced as powder or crystal form and used as an abrasive. Sintering technology can bond it together into very hard ceramics for use as automotive brakes and clutches or bulletproof vest ceramic plates; its density also makes it suitable for long term wear applications while its high melting point helps ensure good thermal conductivity.