Silicon Carbide Ceramics (SiC) is an advanced ceramic material containing silicon and carbon. It occurs in nature as the extremely rare mineral moissanite. Synthetic SiC powders have been produced in large quantities for use as abrasives since 1893. Silicon carbide particles can be sintered together to form very hard ceramics.

With the rapid development of modern national defense, nuclear energy and aerospace technology, automotive industry, and marine engineering, the requirements for materials are getting higher and higher. The development of various new high-performance structural materials is imminent.

Silicon carbide ceramic materials have many excellent characteristics such as high temperature strength, good wear resistance, small coefficient of thermal expansion, high hardness, thermal shock resistance, chemical corrosion resistance, and so on, and are therefore widely used in automotive, machinery, chemical industry. Environmental protection, space technology, information electronics, energy and other fields. Silicon carbide has become an irreplaceable structural ceramic with excellent performance in many industrial fields.

Specifically, silicon carbide ceramics are already widely used as corrosion-resistant containers and pipes in the petrochemical industry, and have been successfully used in the machinery industry for a variety of bearings, cutting tools and mechanical seals. In addition to this, silicon carbide is considered to be the most promising candidate for future production of gas turbines, rocket nozzles and engine components in the aerospace and automotive industries.

When the temperature in the oxygen reaction reaches 1300°C, a protective layer of silicon dioxide forms on the surface of the silicon carbide crystal. With the thickening of the protective layer, the internal silicon carbide is resisted to continue to combine, so that the silicon carbide has good chemical resistance. In terms of acid, alkali and compound resistance, silicon carbide has strong acid resistance and poor alkali resistance due to the role of the protective film of silicon dioxide.

The density of various silicon carbide crystals is similar, usually 3.20 g/mm³. Silicon carbide has a hardness of 9.5 Mohs and a Knoop's hardness of 2670-2815 kg/mm, which is higher than corundum in abrasives and second only to diamond, cubic boron nitride and boron carbide. The thermal conductivity and thermal shock resistance of silicon carbide ceramics are very high, and the thermal expansion parameter is small, so silicon carbide ceramics are a high-quality refractory material.

Industrial silicon carbide ceramics are semiconductors and are impurity conductive. The internal resistance of high purity silicon carbide decreases with increasing temperature. The conductivity of silicon carbide varies with different impurities.

SiC is a compound with strong covalent bonds.The ionic nature of the Si-C bond in SiC is only about 12%. As a result, silicon carbide has high hardness, high modulus of elasticity, and good wear resistance. It is worth pointing out that the silicon dioxide layer formed on the surface of silicon carbide inhibits the further diffusion of oxygen during the oxidation of silicon carbide, so the oxidation rate is low.

Silicon carbide is a carbide accidentally discovered by the American Atchison during his experiments with fused diamonds in 1891. At the time, it was mistaken for a mixture of diamonds.In 1893, Acheson invented a method of industrial smelting of silicon carbide, commonly known as the Acheson furnace. This method is used to this day. It uses a carbonaceous material as a resistive core and electrically heats a mixture of quartz SiO2 and carbon to form silicon carbide.

1905 First discovery of silicon carbide in a meteorite.

1907 The first silicon carbide crystal light-emitting diode is born.

1955 A major breakthrough in theory and technology led to LELY's concept of high-quality carbonization, and since then SiC has been used as an important electronic material.

1958 The first World Conference on Silicon Carbide is held in Boston for academic exchanges.

From 1987 to the present, a silicon carbide production line was established with CREE's research results, and suppliers began to offer commercial silicon carbide substrates.

There are four main application areas of silicon carbide ceramics: functional ceramics, advanced refractories, abrasives and metallurgical raw materials. Silicon carbide raw materials can be supplied in large quantities, can not be considered high-tech products, the application of extremely high technology content of nanometer silicon carbide micropowder can not be formed in a short period of time economies of scale.

(1) As an abrasive, it can be used as abrasive tools, such as grinding wheels, oil stones, grinding heads, and grinding tiles.

(2) As metallurgical deoxidizer and high temperature resistant material.

(3) A high-purity single crystal that can be used in the manufacture of semiconductors and in the manufacture of silicon carbide fibers.

To Good Ceramics is your custom silicon carbide ceramic fabrication specialist for your advanced ceramic prototyping needs. We are always happy to utilize our years of advanced ceramics experience to advise on materials, designs and applications. If you are looking to purchase silicon carbide substrates, rods, tubes, or custom machined parts, please contact us and one of our experts will be happy to assist you!