🧩 PEI+GF20 – Polyetherimide + 20% Glass Fiber (Ultem® GF)
(Reinforced technical material, extremely rigid and thermally stable, capable of continuous operation above 220 °C with minimal deformation. PEI+GF20 is ideal for technical housings where precision is mandatory.)
🔹 What is PEI+GF20
PEI+GF20 is a reinforced version of the Ultem® polymer, where glass fibers reduce shrinkage and increase rigidity and creep resistance by 2–3 times compared to standard PEI. Its main advantages include extreme hardness, near-zero deformation at high temperatures, and inherent flame retardancy (UL94 V-0). Ultem® GF series (GF20, GF30) are industry standards for precision automotive and electrical components.
🔧 Composition & Properties
- Base: 80% Polyetherimide (PEI), 20% Glass Fiber (GF).
- Density: 1.45–1.55 g/cm³.
- Vicat Softening Temperature: ≈ 220–230 °C.
- Chemical Resistance: Excellent (oils, solvents, fuels).
- Continuous Heat Resistance: 210–230 °C.
🚗 Where PEI+GF20 is used in the automotive industry
| Component | Example parts | Observations |
| Engine / Thermal | EGR covers, pumps, sensor housings | Thermal stability up to 230 °C |
| Electrical / Sensors | Sensor plates, ECU mounts | High insulation and rigidity |
| Fuel / Braking | Fittings, valves, pressure parts | Chemically inert, zero shrinkage |
| Technical Structures | Frames, housings, clips | Rigid, flame retardant, easy to machine |
🔧 Welding Temperature and Methods
| Method | Optimal Temp | Observations |
| Hot Air | 350 – 370 °C | Slow melting, uniform controlled flow |
| Plastic Extrusion | 340 – 360 °C | Compatible with PEI or PPS+PEI rods |
| Heat Plate (Mirror) | 340 – 360 °C | Clean bond, zero oxidation |
🔩 Material Compatibility
- ✅ Compatible: PEI, PEI+GF, PPSU, PES, PSU, PPS+PEI, PEEK.
- ⚠️ Good Compatibility: PPS+CF, PPA, PPS+Valox, PPS+Noryl.
- ❌ Incompatible: PP, PE, PS, ABS, PC, PET (completely different melting points).
💡 ReplastMD Recommendation: Use PEI or PPS+PEI rods at 360 °C. Heat uniformly and slowly to avoid burning the glass fibers. Slow cooling helps prevent internal stresses in the welded areas.
🧠 How to Identify PEI+GF20
- Engraved marking: >PEI+GF20<, >ULTEM 2300<, >ULTRASON E GF20<.
- Texture: Matte or semi-glossy, extremely rigid.
- ReplastMD practical test: Heavy part with a slightly rough surface due to glass fiber. Does not deform at 250 °C; burns with a faint imide scent.
🛠️ PEI+GF20 Welding at ReplastMD:
At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional PEI+GF20 welding for EGR components, pumps, and sensors, ensuring a rigid finish resistant up to 230 °C.