What Is Silicon Carbide Used For?

Silicon carbide has many applications and comes in the form of abrasives, ceramic powder and bulletproof armor.

Carborundum (SiC), a crystalline compound of silicon and carbon, is one of the hardest known substances with unique properties that make it beneficial in various industries.

Abrasive

Silicon carbide is hard and brittle, making it an effective abrasive material. Manufacturers utilize it in producing products such as sandpaper; this material comes in different grit sizes from coarse to very fine grit sizes for grinding operations, with coarser ones used to remove large quantities of stock in initial grinding operations while finer ones polish workpiece surfaces to produce smooth finishes.

Abrasive silicon carbide is used in products requiring high endurance, such as car brakes and ceramic plates used in bulletproof vests. Furthermore, this material can also be found in composite materials like carbon fiber-reinforced silicon carbide (CFRC).

Refractory

Silicon carbide is an indispensable raw material in the production of refractory materials. With stable chemical properties, high thermal conductivity, small thermal expansion coefficient and excellent wear resistance it makes an ideal material to create high temperature resistant abrasives such as belt abrasives, sandpaper, grinding wheel wheels and oil stone tools as well as monocrystalline silicon/polycrystalline silicon machine tools.

Metal is very hard and brittle, yet has high thermal and mechanical stability. Composed of silicon atoms surrounded by carbon and oxygen atoms, its composition makes it resistant to heat and mechanical stress as well as having an impressive melting point.

Pure silicon carbide is colorless; industrial grades may range in color from brown to black due to inclusions of iron, aluminium, nitrogen or free carbon. Doping methods exist that create different semiconductors: for instance n-type silicon carbide can be doped with nitrogen or phosphorus while p-type versions can be doped by aluminium, boron or gallium dopants.

Bulletproof Armor

Silicon carbide is one of the hardest materials on Earth. This makes it ideal for bulletproof vests worn by police and military personnel and its thermal properties make it resistant to heat.

Ceramic materials like this one are well known to be strong. Furthermore, ceramic is an excellent conductor of heat and electricity – which makes it perfect for electronic applications like power transistors. Furthermore, corrosion-resistance is another benefit.

Pure silicon carbide possesses a multilayered structure and exists in various polytypes or varieties, each distinguished by their stacking sequence that gives each type its unique physical characteristic – for instance some forms contain covalent bonds between four carbon atoms covalently bound to one silicon atom forming an intricate network structure.

Moissanite is produced synthetically and found only rarely in nature, although small quantities may exist as moissanite jewels. Moissanite plays an essential role in electric vehicles as its ability to withstand high temperatures allows the vehicles to become more energy efficient while decreasing active cooling systems that add weight, cost and complexity.

Semiconductor

Silicon carbide ceramics are versatile nonoxide ceramics used in applications requiring both mechanical and thermal strength, such as wear-resistant parts; refractories for heat resistance; refractory materials to control thermal expansion; and semiconductor electronics devices operating at high temperatures or voltages. Silicon carbide’s hardness makes it suitable for these uses, while its thermal conductivity makes it an effective heat resistant material. Its wide variety of uses extends beyond mechanical applications alone; some examples are: abrasives; wear-resistant parts; refractories for heat resistance; and semiconductor electronics devices operating at high temperatures or voltages respectively.

Crystalline silicon carbide forms in a close-packed structure composed of covalently bonded atoms that form two primary coordination tetrahedra made up of four silicon and four carbon atoms, giving it incredible hardness and strength. Unfortunately it’s insoluble in water or alcohol but resistant to most organic and inorganic acids/salts (with exceptions being hydrofluoric acid and acid fluorides).

Silicon carbide semiconductors boast a wide band gap that allows for much smaller and more efficient devices than equivalent silicon (Si) ones, opening the possibility of their use for power electronics in electric vehicles as well as supporting digitization processes in industrial processes.