Silicon Nitride
Silicon Nitride (Si3N4) provides high thermal shock resistance coupled with a resistance to fracturing. In addition it displays high temperature strength and wear resistance, making it perfectly suited for internal combustion and turbine engine applications.
Silicon Nitride can be manufactured by hot press sintering or preferably using lower temperature methods to avoid dissociation. The sintered material can be worked to produce precise features and high tolerances, usually by diamond grinding.
Silicon Nitride is often considered as one of the most advanced technical ceramics available for extreme applications that require lightness combined with excellent thermal shock resistance and high fracture toughness.
Silicon Nitride applications:
- Turbocharger components
- Ball bearings
- Cutting tools
- Advanced ceramic tubes
- Valve components
- Nozzles
- Seals, seats and bearings
Property | Value |
---|---|
General |
|
Chemical Formula | Si3N4 |
Mechanical |
|
Density | 3.2 - 3.31 g/cm3 |
Hardness | 1500 - 2000 Knoop |
Modulus of Elasticity | 45 - 49 x 106 psi |
Flexural Strength | 65 - 132 kpsi |
Compressive Strength | 435 - 500 kpsi |
Poisson's Ratio | 0.27 |
Fracture Toughness | 4 - 6 MPa m1/2 |
Electrical |
|
Dielectric Strength | 450 V/mil |
Dielectric Constant | 8.4 (@ 1 MHz) |
Volume Resistivity | >1013 Ohm-cm |
Thermal |
|
Coefficient of Thermal Expansion | 3.0 - 3.9 x 10-6/°C |
Thermal Conductivity | 15 - 30 W/mK |
Specific Heat | 0.13 cal/g °C |
Shock Resistance | 750°C Diff |
Maximum Working Temperature | 1250 °C |