🧩 PBT+GF30 – Polybutylene Terephthalate + 30% Glass Fiber
(An ingenious and extremely durable material developed for automotive applications with high mechanical and thermal demands. PBT+GF30 offers superior rigidity, dimensional stability, and excellent resistance to oils, fuels, and vibrations.)
🔹 What is PBT+GF30
PBT+GF30 is a reinforced polyester where 30% of the total mass consists of short glass fibers (GF) uniformly dispersed within the PBT matrix. This composite structure provides exceptional mechanical and thermal strength, along with low shrinkage even after years of use. Compared to PBT+GF20, the 30% fiber version is stiffer but slightly more brittle, requiring precise thermal control during welding for optimal results.
🔧 Composition & Properties
- Base: 70% PBT, 30% Glass Fiber.
- Density: 1.55–1.65 g/cm³.
- Melting Point: ≈ 220–230 °C.
- Chemical Resistance: Excellent (oils, fuels, solvents).
- Continuous Heat Resistance: 140–160 °C.
🚗 Where PBT+GF30 is used in the automotive industry
| Component | Example parts | Observations |
| Engine / Tech Bay | Housings, covers, sensor mounts | Superior thermal resistance and rigidity |
| Electrical Systems | Connectors, ECU housings | Excellent insulation and stability |
| Headlights / Lighting | Frames, LED brackets | Outstanding UV and heat resistance |
| Structural Parts | Clips, technical mounts | High rigidity and hardness |
🔧 Welding Temperature and Methods
| Method | Optimal Temp | Observations |
| Hot Air | 260 – 280 °C | Fast melting, controlled airflow |
| Plastic Extrusion | 250 – 270 °C | Suitable for thick and rigid parts |
| Heat Plate (Mirror) | 250 – 270 °C | Clean bonding, no bubbles |
🔩 Material Compatibility
- ✅ Compatible: PBT, PBT+GF, PC+PBT, PBT+PET, PA+PBT, POM+PBT.
- ⚠️ Good Compatibility: PBT+ASA, PBT+PC, PBT+PA66.
- ❌ Incompatible: PP, PE, PVC, ABS (completely different melting points).
💡 ReplastMD Recommendation: Use PBT+GF or PBT rods at 270 °C. Heat the area uniformly—the high glass fiber content can influence the material’s flow. Avoid overheating to prevent a porous surface appearance.
🧠 How to Identify PBT+GF30
- Engraved marking: >PBT+GF30<, >ULTRADUR<, >CRASTIN<, >VALOX<.
- Texture: Matte, rigid, slightly rough to the touch (fibrous).
- ReplastMD practical test: If the part is rigid, heavy, and has an industrial matte finish, it is PBT+GF30. Burns with a sweet ester scent.
🛠️ PBT+GF30 Welding at ReplastMD:
At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional PBT+GF30 welding for ECU housings and engine mounts, ensuring a solid, heat-resistant, and high-precision finish.