1.Strength with toughness
Dense silicon nitride grades resist crack growth under demanding mechanical loads, while still requiring ceramic-aware design.
Browse Materials
Back to materialsSi3N4
Silicon Nitride
Silicon nitride (Si₃N₄) combines toughness, low mass and thermal-shock resistance for rolling contact, wear components and selected molten-aluminum handling applications.
Gas-pressure sintered and hot-pressed structural ceramics
Core advantages
2.Thermal-shock resistance
Low expansion combined with strength and toughness helps components tolerate rapid temperature changes.
3.Low component mass
A low-density ceramic structure is useful where rotating mass or moving-part weight matters.
4.Wear-resistant surfaces
Hard, precision-finished surfaces suit rolling and sliding contact when lubrication, finish and mating materials are matched.
5.Low wetting by aluminum
Selected grades are used in molten-aluminum handling; alloy composition, fluxes and operating conditions require compatibility checks.
6.Electrical separation
Insulating grades support bearing and tooling designs where unwanted current paths are a concern.
Typical applications
Bearing elements
Balls and rollers combine low mass, wear resistance and stiffness for demanding rolling-contact systems.
Aluminum casting
Riser tubes and immersion components exploit thermal-shock resistance and low wetting in qualified aluminum-melt processes.
Welding and positioning
Location pins and rollers provide wear-resistant, electrically insulating contact points during repeated heating cycles.
Pumps and seals
Wear components can combine mechanical durability with chemical resistance after fluid and load compatibility are established.
Thermal fixtures
High-temperature fixtures and structural parts benefit from low expansion and thermal-shock resistance; atmosphere and loading set the service envelope.
Material comparison
| Material / route | Density (g/cm³) | Bending strength (MPa) | Conductivity (W/(m·K)) | Material distinction |
|---|---|---|---|---|
| Dense structural Si₃N₄ | 3.21 g/cm³ | 1,000 MPa (4-point, 20°C) | 34 W/(m·K), 20°C | Dense structural grade; published fracture toughness 6.5 MPa·√m. |
| Direct-sintered SiC | 3.15 g/cm³ | 480 MPa (4-point, 20°C) | 150 W/(m·K), 20°C | Direct-sintered SiC reference; prioritizes hardness and heat transfer, not the same toughness profile. |
| High-conductivity AlN | 3.30 g/cm³ | 300 MPa (4-point, 20°C) | 180 W/(m·K), 20°C | Thermal-management reference with electrical insulation, not a direct structural substitute. |
Manufacturing processes and design options
Gas-pressure sintering
A dense structural route for shaped components; grade selection balances strength, toughness and thermal behavior.
Hot pressing or HIP
Pressure-assisted routes reduce porosity; choose the route around component geometry and required performance.
Reaction bonding
Low dimensional change supports near-net shapes, but residual porosity changes strength and suitability for sealed service.
Diamond finishing
Post-sinter grinding and lapping establish dimensions and surface quality for bearing, sealing and locating features.
Match the grade to temperature, atmosphere, cyclic loading and chemical exposure. Molten-aluminum compatibility is not resistance to every metal or flux. Reaction-bonded and dense sintered materials are not interchangeable.
Process availability and acceptance criteria are confirmed for the selected component.
Request a Si3N4 component quote
Send the drawing, quantity, medium, temperature cycle, load and critical surfaces. Material route and process options are confirmed for the selected part.
Request a quote