🧩 PEEK – Polyether Ether Ketone
(Ultra-technical, semi-crystalline material with extreme performance, capable of continuous operation at 250–260°C and short-term peaks up to 300°C. PEEK combines the mechanical strength of metals with the lightweight properties of elite polymers.)
🔹 What is PEEK
PEEK (Polyether Ether Ketone) is a high-performance thermoplastic from the polyaryletherketone (PAEK) family. It is arguably the most capable plastic in existence, offering aluminum-like strength, total chemical inertness to oils and solvents, and incredible resistance to steam and wear. It is used in applications where even high-end materials like PEI or PPSU would fail.
🔧 Composition & Properties
- Base: 100% Polyether Ether Ketone.
- Density: 1.30–1.32 g/cm³.
- Melting Point: ≈ 343 °C.
- Chemical Resistance: Exceptional (nearly inert).
- Continuous Heat Resistance: 250–260 °C.
🚗 Where PEEK is used in the automotive industry
| Component | Example parts | Observations |
| Engine / Thermal | Bearings, bushings, pumps | Operates at 250 °C, replaces aluminum |
| EGR / Fuel Systems | Fittings, nozzles, gaskets | Chemically inert, zero shrinkage |
| Electrical / Sensors | Mounts, covers, insulators | High insulation and rigidity |
| Transmission | Friction parts, spacers | Superior wear and abrasion resistance |
🔧 Welding Temperature and Methods
| Method | Optimal Temp | Observations |
| Hot Air | 360 – 400 °C | Slow melting, dense and viscous flow |
| Plastic Extrusion | 370 – 400 °C | PEEK or PEEK-GF/CF rods |
| Heat Plate (Mirror) | 370 – 390 °C | Clean bond, no oxidation |
🔩 Material Compatibility
- ✅ Compatible: PEEK, PEEK+GF, PPS, PPSU, PES, PEI, PSU.
- ⚠️ Good Compatibility: PPS+PEI, PPS+CF, PPA.
- ❌ Incompatible: PP, PE, PS, ABS, PC, PET (completely different melting points).
💡 ReplastMD Recommendation: Use pure PEEK rods at 380°C. Heat slowly and uniformly to prevent oxidation. Gradual cooling is mandatory to avoid internal stresses and micro-cracks in the weld area.
🧠 How to Identify PEEK
- Engraved marking: >PEEK<, >VICTREX<, >VESTAKEEP<, >TECAPEEK<.
- Texture: Matte or semi-glossy, extremely rigid and heavy feel.
- ReplastMD practical test: If the part is rock-rigid and does not soften even under 250°C hot air, it is confirmed. Burns with a faint ketone scent.
🛠️ PEEK Welding at ReplastMD: At our ReplastMD service center (Chisinau, Ciocana sector), we perform professional PEEK welding for pumps, valves, and EGR components, ensuring an industrial-grade, high-strength finish.