🧩 POM+SiO₂ – Polyacetal (Delrin) with Silicon Dioxide
(A polyacetal composite modified with silicon dioxide (SiO₂) microparticles, designed for applications requiring low wear, high rigidity, and precision dimensional stability.)
🔹 What is POM+SiO₂
POM+SiO₂ combines the self-lubricating properties of POM with the mineral hardness of silicon dioxide. Adding nanoparticles of SiO₂ increases surface hardness and resistance to abrasion and dry friction, even without external lubricants. This material is widely used in precision mechanisms, technical gears, and sliding components.
🔧 Composition
| Component | Typical Ratio | Role |
| Polyacetal (POM) | ≈ 95 % | Main low-friction matrix |
| Silicon Dioxide (SiO₂) | ≈ 3–5 % | Reinforcement, wear reduction, increased stiffness |
| Additives | < 2 % | Protection against degradation and oxidation |
🚗 Where POM+SiO₂ is used in the automotive industry
| Component | Example parts | Observations |
| Sliding Parts / Guides | VW, Ford | Low wear, maintenance-free |
| Fine Gears | Renault, Toyota | Silent operation and high precision |
| Liquid Fittings / Valves | Bosch, Valeo | Dimensionally stable and oil resistant |
| ABS Sliders / Clips | Dacia, Peugeot | Controlled elasticity, low friction |
🔧 Welding Temperature and Methods
| Method | Optimal Temp | Observations |
| Hot Air | 250 – 270 °C | Easy to weld, uniform melting |
| Heat Plate (Mirror) | 250 – 265 °C | Ideal – Smooth surface, no oxidation |
| Plastic Extrusion | 260 °C | Recommended – use compatible POM rod |
🔩 Material Compatibility
- ✅ Compatible: POM, POM-C, POM-H.
- ⚠️ Partially Compatible: POM+PTFE, POM+SiO₂ (requires preheating).
- ❌ Incompatible: PA, PP, PE, ABS (chemically and thermally incompatible).
💡 ReplastMD Recommendation: Weld at ~260 °C using pure POM or identical POM+SiO₂ rods. The material offers great wear resistance and precision, perfect for fine friction mechanisms.
🧠 How to Identify POM+SiO₂
- Engraved marking: > POM+SiO₂ <, > DELRIN Si <, > ULTRAFORM Si <.
- Texture: Smooth, hard, with a satin-like gloss.
- ReplastMD practical test: Very clean, glossy edges when cut, no burrs. Flame: burns rapidly with a sharp formaldehyde scent.
🛠️ POM+SiO₂ Welding at ReplastMD:
At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional POM+SiO₂ welding for fine-motion mechanisms and technical fittings, ensuring a high-durability finish.