Silicon nitride (Si₃N₄) locating pin is a high-precision positioning component made of high-performance silicon nitride ceramic raw material, manufactured through precision forming, sintering and post-processing.
Widely applied in mold positioning, workpiece positioning, assembly datum and precision mechanical connection scenarios under harsh working conditions such as high temperature, corrosion and abrasion, it possesses comprehensive superiorities including high temperature resistance, corrosion resistance, high hardness and electrical insulation, which are incomparable to metal locating pins.
Used as a long-term stable positioning and guiding component in aluminum alloy casting, powder metallurgy sintering furnaces, chemical equipment, electronic packaging equipment and aerospace precision mechanisms, silicon nitride locating pins can greatly improve equipment reliability and service life.
| Test item | Unit | Index range |
| Bulk Density | g/cm³ | 3.2 |
| Porosity | % | ＜1.5 |
| Flexural Strength | MPa | ≥700 |
| Compressive Strength | MPa | ≥2800 |
| Young's Modulus | GPa | 260~280 |
| Fracture Toughness | MPa·m¹/² | ≥6.5 |
| Vickers Hardness (HV10) | kgf/mm² | 1400-1500 |
| Coefficient of Thermal Expansion (20–1000°C) | ×10⁻⁶ /K | 3.2~3.4 |
| Thermal Conductivity | W/(m·K) | 16~22 |
| Recommended Maximum Operating Temperature (Air) | ℃ | 1200 |
1. Excellent High-Temperature Resistance: Can operate stably for extended periods at temperatures below 1200°C without softening, oxidizing, or deforming.
2. Extremely High Hardness and Wear Resistance: Vickers hardness (HV) of 1400–1500, far exceeding that of stainless steel and alloy steel; maintains dimensional stability during long-term use with minimal wear.
3. Strong Corrosion Resistance: Except for hydrofluoric acid and concentrated strong alkalis, it is inert to most acid, alkali, and salt solutions, as well as molten non-ferrous metals (such as aluminum, zinc, and copper).
4. Excellent Electrical Insulation Properties: High volume resistivity makes it suitable for positioning applications requiring electrical isolation.
5. Low thermal expansion coefficient: The thermal expansion coefficient is approximately 3.2×10⁻⁶ /K (20–1000°C), providing good compatibility with various ceramic and metallic materials.
6. Non-magnetic and non-contaminating: It does not interfere with precision electronic components or optical systems and does not produce metal ion contamination.
7. High thermal shock resistance: It can withstand severe thermal cycling without cracking.
1. High-temperature mold positioning: Guide pins and locating pins in aluminum alloy die-casting molds, magnesium alloy die-casting molds, and copper alloy casting molds.
2. Powder metallurgy sintering furnaces: Positioning of in-furnace fixtures and material trays.
3. Corrosion-resistant chemical processing equipment: Positioning of internal components in reactors and guidance of internal parts in towers.
4. Electronic Packaging and Semiconductor Equipment: Precision positioning in non-magnetic, anti-static environments.
5. Aerospace Engine Component Assembly: High-temperature-resistant, wear-resistant positioning connections.
6. Glass and Ceramic Thermal Processing Equipment: Kiln car positioning and kiln furniture positioning.
7. Vacuum Furnaces and High-Temperature Testing Equipment: Non-volatile, non-contaminating properties in vacuum environments.
