Silicon nitride part is made of a high-melting-point ceramic material that is extremely hard and relatively chemically inert. Due to the even performance in high temperature, Si3N4 is a commonly used ceramic material in the metallurgical industry. Silicon nitride part has excellent thermal shock resistance due to the microstructure. The creep and oxidation resistance of Si3N4 is also superior, its low thermal conductivity and high wear resistance also make it an outstanding material that can withstand conditions of most industrial applications.
High strength over a large temperature range
High fracture toughness
Good flexural strength
Mechanical fatigue & creep resistant
Lightweight – Low density
High hardness and wear resistance, both impingement and frictional modes
Superior thermal shock resistance
Low thermal expansion
Electrical insulator
Good oxidation resistance
Good chemical corrosion resistance
Wear resistant
High stiffness
Silicon nitride can be machined in green, biscuit, or fully dense states. While in the green or biscuit form it can be machined relatively easily into complex geometries. However, the sintering process that is required to fully densify the material causes the silicon nitride body to shrink approximately 20%. This shrinkage means that it is impossible to hold very tight tolerances when machining silicon nitride pre-sintering. In order to achieve very tight tolerances, fully sintered material must be machined/ground with diamond tools. This processes uses a very precise diamond coated tool/wheel to abrade away the material until the desired form is created. Due to the inherent toughness and hardness of the material, this can be a time-consuming and costly process.
| Properties | Units | Value |
| Density, r | g/cm3 | 3.31 |
| Color | – | dark gray |
| Water Absorption | % @R.T. | 0.0 |
| Hardness | Moh’s | 9 |
| Hardness | knoop (kg/mm2) | 2200 |
| Compressive Strength | MPa @ R.T. | 689-2760 |
| Tensile Strength | MPa @ R.T. | 360-434 |
| Modulus of Elasticity (Young’s Mod.) |
GPa | 317 |
| Flexural Strength (MOR) | MPa @ R.T. | 679-896 |
| Fracture Toughness, KIc | MPa x m1/2 | 5.0-8.0 |
| Max. Use Temperature (* denotes inert atm.) |
ºC | 1500 |
| Thermal Shock Resistance | DT (ºC) | 750 |
| Thermal Conductivity | W/m-K @ R.T. | 27 |
| Coefficient of Linear Thermal Expansion, al | mm/m-ºC (~25ºC through ±1000ºC) | 3.4 |
| Specific Heat, cp | cal/g-ºC @ R.T. | 0.17 |
| Dielectric Constant | 1MHz @ R.T. | 7.0 |
| Dielectric Strength | kV/mm | 17.7 |
| Electrical Resistivity | Wcm @ R.T. | 1013 |
Applications:
Rotating ball & rollers bearings
Cutting tools
Engine components: valves, rocker arm pads, seal faces
Induction heating coil supports
Turbine blades, vanes, buckets
Welding & brazing jigs
Heating Element components
Crucibles
Metal tube forming rolls and dies
TIG / Plasma welding nozzles
Weld positioners
Precision shafts and axles in high wear environments
Thermocouple sheaths & tubes
Semiconductor Process Equipment
Our silicon nitride parts/components are exported to USA, Canada, Europe, and South America and Southeast Asia.
After-sales service:
Accept any repair of the product, help to improve technology for customer. And also provide long-term technical help and support for you.
