Silicon Carbide, SiC Ceramic Properties
Silicon Carbide is the only chemical compound of carbon and silicon. It
was originally produced by a high temperature electro-chemical reaction
of sand and carbon. Silicon carbide is an excellent abrasive and has
been produced and made into grinding wheels and other abrasive products
for over one hundred years. Today the material has been developed into a
high quality technical grade ceramic with very good mechanical
properties. It is used in abrasives, refractories, ceramics, and
numerous high-performance applications. The material can also be made an
electrical conductor and has applications in resistance heating, flame
igniters and electronic components. Structural and wear applications are
constantly developing.
.Key
Silicon Carbide Properties | |
Low density | |
High strength | |
Low thermal expansion | |
High thermal conductivity | |
High hardness | |
High elastic modulus | |
Excellent thermal shock resistance | |
Superior chemical inertness |
.
Silicon Carbide Typical Uses | |
Fixed and moving turbine components | |
Suction box covers | |
Seals, bearings | |
Ball valve parts | |
Hot gas flow liners | |
Heat exchangers | |
Semiconductor process equipment |
General Silicon Carbide Information
Silicon carbide is composed of tetrahedra of carbon and silicon atoms
with strong bonds in the crystal lattice. This produces a very hard and
strong material. Silicon carbide is not attacked by any acids or alkalis
or molten salts up to 800°C. In air, SiC forms a protective silicon
oxide coating at 1200°C and is able to be used up to 1600°C. The high
thermal conductivity coupled with low thermal expansion and high
strength give this material exceptional thermal shock resistant
qualities. Silicon carbide ceramics with little or no grain boundary
impurities maintain their strength to very high temperatures,
approaching 1600°C with no strength loss. Chemical purity, resistance to
chemical attack at temperature, and strength retention at high
temperatures has made this material very popular as wafer tray supports
and paddles in semiconductor furnaces. The electrical conduction of the
material has lead to its use in resistance heating elements for electric
furnaces, and as a key component in thermistors (temperature variable
resistors) and in varistors (voltage variable resistors).
Download Silicon Carbide datasheet
Silicon Carbide Engineering Properties*
Silicon Carbide Properties |
Mechanical |
SI/Metric (Imperial) |
SI/Metric |
(Imperial) |
Density |
gm/cc (lb/ft3) |
3.1 |
(193.5) |
Porosity |
% (%) |
0 |
(0) |
Color |
— |
black |
— |
Flexural Strength |
MPa (lb/in2x103) |
550 |
(80) |
Elastic Modulus |
GPa (lb/in2x106) |
410 |
(59.5) |
Shear Modulus |
GPa (lb/in2x106) |
— |
— |
Bulk Modulus |
GPa (lb/in2x106) |
— |
— |
Poisson’s Ratio |
— |
0.14 |
(0.14) |
Compressive Strength |
MPa (lb/in2x103) |
3900 |
(566) |
Hardness |
Kg/mm2 |
2800 |
— |
Fracture Toughness KIC |
MPa•m1/2 |
4.6 |
— |
Maximum Use Temperature (no load) |
°C (°F) |
1650 |
(3000) |
Thermal | | | |
Thermal Conductivity |
W/m•°K (BTU•in/ft2•hr•°F) |
120 |
(830) |
Coefficient of Thermal Expansion |
10–6/°C (10–6/°F) |
4.0 |
(2.2) |
Specific Heat |
J/Kg•°K (Btu/lb•°F) |
750 |
(0.18) |
Electrical | | | |
Dielectric Strength |
ac-kv/mm (volts/mil) |
— |
semiconductor |
Dielectric Constant |
— |
— |
— |
Dissipation Factor |
— |
— |
— |
Loss Tangent |
— |
— |
— |
Volume Resistivity |
ohm•cm |
102–106 |
dopant dependent |
*All properties are room temperature values except as noted.
The data presented is typical of commercially available material and is
offered for comparative purposes only. The information is not to be
interpreted as absolute material properties nor does it constitute a
representation or warranty for which we assume legal liability. User
shall determine suitability of the material for the intended use and
assumes all risk and liability whatsoever in connection therewith.
Back to top
Standard Products | Custom Products and
Services | Case Studies |
Materials Design Notes
| Working Together |
Vision | Contact Us |
Site Map
1-908-213-7070
© 2013 Accuratus
Site Design M. Adams |