🧩 PEI+PEEK – Polyetherimide + Polyether-Ether-Ketone
(Top-tier technical material, naturally reinforced, with exceptional thermal and mechanical stability. Used in precision automotive parts, structural components, and exhaust systems exposed to extreme heat.)
🔹 What is PEI+PEEK
PEI+PEEK is a high-performance hybrid material created by combining two elite super-plastics. PEI provides rigidity and dimensional stability, while PEEK offers mechanical, thermal, and chemical resistance at the highest possible level for polymers. This blend is designed for extreme performance, specifically where temperatures exceed 230 °C and where other materials would warp or degrade.
🔧 Composition & Properties
- Composition: 50–70% Polyetherimide (PEI), 30–50% Polyether-Ether-Ketone (PEEK).
- Density: 1.40–1.47 g/cm³.
- Vicat Softening Temperature: ≈ 250 °C.
- Chemical Resistance: Total resistance to oils, fuels, and industrial solvents.
- Continuous Heat Resistance: 230–250 °C.
🚗 Where PEI+PEEK is used in the automotive industry
| Component | Example parts | Observations |
| Engine / Thermal | EGR covers, pumps, mounts | Continuous operation above 230 °C |
| Exhaust / Fuel | Fittings, distributors, EGR valves | High pressure and chemical resistance |
| Electrical / ECU | Pressure sensors, thermal modules | Dimensional stability and insulation |
| Structural OEM | Frames, clips, supports | Exceptional mechanical strength |
🔧 Welding Temperature and Methods
| Method | Optimal Temp | Observations |
| Hot Air | 370 – 390 °C | Slow melting, stable flow |
| Plastic Extrusion | 360 – 380 °C | PEI+PEEK or pure PEEK rod |
| Heat Plate (Mirror) | 360 – 380 °C | Clean bond, no carbonization |
🔩 Material Compatibility
- ✅ Compatible: PEI, PEI+GF, PPSU, PES, PSU, PPS+PEI, PEEK.
- ⚠️ Good Compatibility: PPS, PPS+CF, PEI+PC.
- ❌ Incompatible: PP, PE, PS, ABS, PVC, PMMA (completely different melting points).
💡 ReplastMD Recommendation: Use PEI+PEEK or pure PEEK rods at 380 °C. Uniform heating and slow cooling are essential to avoid internal stresses and maintain the structural clarity of the welded zone. Surface preparation is critical for optimal adhesion.
🧠 How to Identify PEI+PEEK
- Engraved marking: >PEI+PEEK<, >ULTRASON PEEK<, >TECAPEEK<.
- Texture: Matte or semi-glossy, dense and extremely rigid.
- ReplastMD practical test: Heavy part, very stiff. Does not deform even at 250 °C; burns with a clean flame and a faint aromatic scent.
🛠️ PEI+PEEK Welding at ReplastMD:
At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional PEI+PEEK welding for EGR components and technical pumps, ensuring a dense, stable finish resistant up to 250 °C.