Silicon carbide (SiC), sometimes nicknamed “carborundum”, is a ceramic compound composed of silicon and carbon atoms. Naturally occurring silicon carbide is found as the rare mineral moissanite. Since 1893, synthetic silicon carbide powder has been widely adopted as an abrasive material.
When sintered, SiC powder forms extremely hard ceramic grains. These are incorporated into high-wear-resistant components including automotive brake pads, clutch parts and ballistic protective vests. Historically, silicon carbide was also applied to fabricate electronic components such as early radio detectors and light-emitting diodes. At present, it is a core material for high-temperature and high-voltage semiconductor devices.
Silicon carbide Chemical Properties
| Melting point | 2700 °C (lit.) |
| density | 3.22 g/mL at 25 °C (lit.) |
| refractive index | 2.65 |
| solubility | Soluble in molten sodium hydroxide, potassium hydroxide and in molten iron. |
| form | nanopowder |
| color | Green |
| Specific Gravity | 3.22 |
| Resistivity | 107–200 (ρ/μΩ.cm) |
| Water Solubility | Soluble in molten alkalis (NaOH, KOH) and molten iron. Insoluble in water. |
| Crystal Structure | Cubic, Sphalerite Structure - Space Group F(-4)3m |
| Hydrolytic Sensitivity | 1: no significant reaction with aqueous systems |
| Merck | 148492 |
| Exposure limits | ACGIH: TWA 10 mg/m3; TWA 3 mg/m3; TWA 0.1 fiber/cm3 |
| OSHA: TWA 15 mg/m3; TWA 5 mg/m3 | |
| NIOSH: TWA 10 mg/m3; TWA 5 mg/m3 | |
| Stability: | Stability |
| InChIKey | HBMJWWWQQXIZIP-UHFFFAOYSA-N |
| IARC | 2A (Vol. 111) 2017 |
| NIST Chemistry Reference | Silicon monocarbide(409-21-2) |
| EPA Substance Registry System | Silicon carbide (409-21-2) |
| Hazard Codes | Xi |
| Risk Statements | 36/37/38 |
| Safety Statements | 26-36 |
| OEB | B |
| OEL | TWA: 10 mg/m3 (total) |
| WGK Germany | 3 |
| RTECS | VW0450000 |
| TSCA | Yes |
| HS Code | 28492000 |
| Hazardous Substances Data | 409-21-2(Hazardous Substances Data) |
Product Application of Silicon carbide CAS#409-21-2
Thanks to its outstanding thermal stability, superior mechanical strength and excellent thermal conductivity, silicon carbide finds broad applications in nuclear energy components, chemical processing equipment, high-temperature process systems, electric heating elements and resistors. It is also a preferred material for abrasives, grinding tools, high-grade refractories and advanced fine ceramics.
