One material, many forms. All products are made from our controlled Si₃N₄ powder and qualified to the same reliability standard.
High-purity α-phase Si₃N₄ powder optimized for pressing, slip casting and injection molding. Controlled particle size and oxygen content give predictable sintering and final properties.
Complex GPS / HIP sintered components manufactured to drawing — nozzles, sheaves, insulators, fixtures and custom geometries.
| Property | Typical value | Method |
|---|---|---|
| Density | ≥ 3.20 g/cm³ | Archimedes |
| Flexural strength (4-pt) | 600 – 1000 MPa | ISO 14704 |
| Hardness (HV10) | 1500 – 1800 | Vickers |
| Fracture toughness K₁C | 5 – 8 MPa·m¹/² | SEPB / Indentation |
| Thermal expansion (RT–1000°C) | ~3.0–3.3 ×10⁻⁶/K | Dilatometry |
| Thermal conductivity (RT) | 15 – 80 W/m·K | Laser flash |
| Max service temp (air) | ~1000 – 1200 °C | — |
Typical ranges; exact values depend on grade and sintering route. COA provided per batch.
Si₃N₄ balls for hybrid bearings — about 60% lighter than steel, harder, corrosion-resistant and electrically insulating. Enable higher speeds, lower friction and longer life in spindles, turbines and machine tools.
Silicon nitride's high strength and good thermal conductivity make it the leading substrate for AMB (active metal brazed) packages in SiC IGBT / power modules — surviving thermal cycling that cracks Al₂O₃ and AlN.
| Property | Si₃N₄ (AMB) | Why it matters |
|---|---|---|
| Bending strength | ≥ 600 MPa | Survives thermal cycling |
| Thermal conductivity | ≥ 80 W/m·K | Dissipates module heat |
| Thermal expansion | ~3.0 ×10⁻⁶/K | Matches SiC chip |
| Size | Up to ~ 140 × 190 mm | Module footprint |
Si₃N₄ indexable inserts and tool blanks for high-speed machining of cast iron, nickel superalloys and hardened steels. The material's hot hardness, thermal shock resistance and chemical stability allow higher cutting speeds and longer tool life than coated carbide in interrupted cuts and dry machining.
Sialon is a silicon nitride solid solution alloyed with aluminium and oxygen. It retains Si₃N₄'s thermal shock resistance while adding higher toughness, lower thermal expansion and outstanding anti-welding behaviour — making it a top choice for machining grey cast iron and nickel-based alloys.
| Property | Typical value | Why it matters |
|---|---|---|
| Hardness (HV10) | 1600 – 1800 | Long edge life |
| Fracture toughness K₁C | 6 – 9 MPa·m¹/² | Resists chipping |
| Thermal expansion | ~3.0 ×10⁻⁶/K | Stable under heat |
| Colour | Golden-tan | Identifies Sialon grade |
Beyond standard products, we manufacture silicon nitride components for specific environments where wear, corrosion, electrical insulation or micron-level precision decide service life and downtime.
Silicon nitride's hardness (HV 1500–1800) and corrosion resistance make it ideal for abrasive duty — wear liners, cyclone components, nozzles and pulverizer parts in slurry and ore handling. It outlasts steel and alumina, cuts downtime and adds no metal contamination.
In semiconductor test, Si₃N₄ thin plates act as insulating, dimensionally stable spacers and guides inside probe-card assemblies (space transformers / MLBs). Near-zero thermal expansion and high flatness keep contacts aligned across temperature cycles.
For flip-chip / bump bonding, precision Si₃N₄ alignment pins and posts locate the chip or wafer during bonding. High stiffness, tight tolerance, electrical insulation and non-magnetic behavior prevent shorts and hold micron accuracy under heat.
Si₃N₄ plungers, check-valve seats and balls serve reciprocating and metering pumps in chemical, seawater and abrasive slurries. Harder and more corrosion-resistant than metal or alumina, they run longer with less lubrication and no seizing.
Silicon nitride survives molten aluminium without wetting or reacting — the basis for a family of consumables and bearings that cut downtime and scrap in die casting and high-speed rotation.
In low-pressure die casting, Si₃N₄ thermocouple protection tubes resist molten aluminium, thermal shock and erosion far longer than steel or iron — keeping temperature sensing accurate and protecting the element.
Si₃N₄ heater protection sleeves shield immersion heaters from molten aluminium and dross, extending heater life and preventing breakage that would contaminate the bath.
For low-pressure casting, the Si₃N₄ riser (liquid-metal feed) tube is non-wetting to aluminium and resists thermal cycling, delivering stable, contamination-free metal feed with long service life.
Si₃N₄ rotors and shafts for aluminium degassing spin without eroding in molten metal, removing hydrogen more efficiently than graphite and lasting far longer — less downtime, cleaner melt.
Hybrid bearings pair Si₃N₄ balls with steel rings — lighter, stiffer, faster and electrically insulating versus all-steel. Standard in machine-tool spindles, turbines and EV drive units.
All-ceramic bearings use Si₃N₄ rings and balls for maximum corrosion, magnetic and electrical insulation — ideal for vacuum, cleanroom, medical and aggressive chemical duty.
All items are quoted on request by specification, grade and order volume. Email dolphintec@aliyun.com for a formal quotation.
Send your drawing and duty cycle — we'll recommend a grade and process.
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