Aug 20 2013
Topics Covered
Description
Applications
Chemical Properties
Electrical Properties
Thermal, Mechanical and Optical Properties
Safety Information
Description
Silicon carbide is a compound of silicon and carbon with the chemical formula SiC. It occurs in the extremely rare mineral moissanite. Silicon carbide grains are bonded together by sintering to form hard ceramics that are used in applications requiring high endurance. SiO2 present in plant material can be used to produce silicon carbide with high surface area.
Applications
Silicon carbide finds applications in the following:
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Graphene and steel production
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Carborundum printing technique
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Jewelry making
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Nuclear fuel cladding
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Thin filament pyrometry
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LEDs and automobile parts
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Abrasive and cutting tools.
Chemical Properties
The chemical properties of silicon carbide are provided in the table below:
Chemical Properties |
Chemical Formula |
SiC |
Molecular Weight |
40.10 |
CAS No. |
409-21-2 |
Group |
Silicon – 14
Carbon - 14 |
Crystal Structure |
Hexagonal |
Symmetry Group |
C46v-P63mc |
Lattice Constant |
a=3.076 Å
c=10.053 Å |
Electrical Properties
The electrical properties of silicon carbide are provided in the table below:
Electrical Properties |
Dielectric Constant |
9.6 |
Band Gap |
3.26 eV |
Electron Mobility |
800 cm2/Vs |
Hole Mobility |
115 cm2/Vs |
Electron Diffusion Coefficient |
≤22 cm2/s |
Hole Diffusion Coefficient |
≤3 cm2/s |
Electron Thermal Velocity |
1.9 x 105 m/s |
Hole Thermal Velocity |
1.2 x 105 m/s |
Thermal, Mechanical and Optical Properties
The thermal, mechanical and optical properties of silicon carbide are provided in the tables below:
Thermal Properties |
Specific Heat Capacity |
0.2926 J/g°C |
Thermal Diffusivity |
1.7 cm2 s-1 |
Debye Temperature |
1027°C |
Mechanical Properties |
Density |
3.21 g/cm3 |
Melting Point |
3103 ± 40 K |
Surface Microhardness |
2900-3100 kg mm-2 |
Mohs Hardness |
~9 |
Optical Properties |
Refractive Index |
2.56 |
Optical Photon Energy |
104.2 meV |
Safety Information
Safety Information |
GHS Hazard Statements |
H315 - Causes skin irritation
H319 - Causes serious eye irritation
H335 - May cause respiratory irritation. |
Safety Precautions |
P261 - Avoid breathing dust/ fume/ gas/ mist/ vapors/ spray
P305 + P351 + P338 - If in eyes: Rinse cautiously with water for several minutes. Remove contact lenses, if present and easy to do. Continue rinsing. |