Silicon Carbide Powder

Silicon carbide powder is an extremely durable abrasive and refractory material used in high temperature electronic device production.

Production involves heating silica sand with carbon sources such as petroleum coke in an electric arc furnace to form both black and green silicon carbides; black silico has iron impurities, producing darker hues in its finish.

Properties

Silicon carbide (SiC) is an industrial mineral composed of silicon and carbon that has found widespread application for industrial use as an abrasive – from sandpaper and grinding wheels, to industrial furnace linings and bulletproof vest ceramic plates, as well as semiconductor substrates for light emitting diodes (LEDs). SiC also occurs naturally as moissanite mineral. SiC can also be found naturally as moissanite mineral. SiC can also be found naturally as moissanite. SiC has many applications including use as refractory linings for industrial furnaces as well as ceramic plates used with bulletproof vests for light emitting diodes – it even exists naturally as moissanite mineral.

Aluminum boasts excellent abrasion resistance, withstanding temperatures up to 1400 degC without significantly degrading in strength. Furthermore, its corrosion resistance extends to most common inorganic acids, salts and alkalis; however it may corrode under certain circumstances such as when coming in contact with acid fluorides or hydrofluoric acids.

SiC is an electrically insulating material with high tensile strength and low specific gravity that’s both chemically stable and electrically insulating properties, offering good chemical stability as well as non-magnetic characteristics. It melts at 2080 degC. SiC’s close-packed structure allows tetrahedral coordination between silicon and carbon atoms for high strength-to-weight ratio and thermal conductivity properties.

Powders of silicon carbide can be made to achieve various purity levels, crystal structures and particle sizes. They can be produced using various processes – carbothermal reduction through Acheson’s process or polymer conversion as well as high temperature gas phase chemical reactions – with various methods leading to their creation. Once prepared, these powders can be used in manufacturing ceramic articles such as refractory shapes for industrial furnaces or electrical insulation elements for electronics devices such as microprocessors.

Applications

Silicon carbide powder can be utilized in numerous applications. As a very tough material with superior thermal conductivity and chemical resistance, silicon carbide withstands extreme temperatures ranging from molten glass up to 1,400degC (2,552degF). Silicon carbide is frequently found as part of refractories such as ceramics, glass and kiln furnace walls – and even grinding wheels and sandpaper are manufactured using its additive. In addition, silicon carbide serves as an integral material in high temperature semiconductors and electronics applications.

Carbon can also be found in composite materials like carbon fiber-reinforced silicon carbide (CFRC), which is commonly found in automobile brakes and bulletproof vests due to its excellent tensile strength and ability to withstand high-velocity impacts.

Sintered silica is often produced using high-pressure sintering at temperatures reaching up to 11,000degC (1,815degF). The final product features an extremely tightly packed structure composed of four silicon and four carbon atoms bonded together in a tetrahedral arrangement, non-magnetic properties and can resist most chemicals including aliphatic hydrocarbons, alkalis, organic acids and molten salts; however it cannot withstand strong oxidizing agents such as hydrofluoric acid and potassium fluoride.

Preparation

Silicon Carbide is an extremely hard refractory material used in applications including grinding wheels, whetstones, cutting tools, sandblasting, water jet cutters and ceramics. Additionally, it plays an integral part in high temperature kilns used to fire glasses and ceramics at high temperatures. Available in various particle sizes for specific uses as well as black or white forms – most popularly the former (Wurtzite crystal structure) and latter (Zinc Blende)

A powder of a-SiC has a hexagonal crystal structure and Mohs hardness rating of 7. It can withstand extreme conditions with its high melting point and strong thermal conductivity, and has no toxicity issues or insoluble characteristics in water or alcohol. Furthermore, its resistance against organic acids, alkalis, salts and acid fluorides makes it suitable for many uses in industry and engineering applications.

Advanced applications require larger single crystals of b-SiC to be produced using the Lely method, so that these may then be cut into gems known as synthetic moissanite. SiC can also be bonded together using resins or polymers into fibers used for reinforcing metals and other materials.

The invention relates to a process for manufacturing b-SiC powders by mixing a Si source comprising Si and C with an excess of carbon, heating the composition, and then filtering, washing, and drying it. Once completed, these b-SiC powders can be easily pulverized through subsequent processes such as filtration washing drying.

Storage

Silicon carbide is one of the world’s hardest substances, rivaling diamond and boron carbide in terms of hardness. Used in applications that demand thermal and mechanical properties such as wear-resistant materials, refractories, ceramics, semiconductors and semiconductor abrasives and wear-resistant applications; wear-resistant coatings; thermal shock resistance; low thermal expansion rates and high electrical conductivity, silicon carbide offers exceptional strength, durability and electrical conductivity properties that make it a versatile material choice.

Aerospace industries rely heavily on SiC powder components that withstand extreme heat and pressure, including brake systems used in automobiles to improve performance while decreasing wear on rotors and drums. Meanwhile, semiconductor industries use it in wafer processing equipment to manage heat more effectively, as well as for bulletproof vest ceramic plates which protect soldiers from high-velocity impacts.

Black silicon carbide is made in an electric resistance furnace at high temperatures using quartz sand and petroleum coke as primary raw materials. It has an average hardness between fused alumina and synthetic diamond and can be used as an abrasive material when processing low tensile strength materials like cast iron, nonferrous metals, rock, leather and rubber. Furthermore, black silicon carbide is often utilized in producing refractory materials and metallurgical additives.