When PEEK earns its cost
PEEK runs continuously at 250 °C, resists almost every industrial solvent, is biocompatible (implant-grade variants exist), and approaches the specific strength of aluminum. The downsides: filament costs $400–$800 per kilogram, and the printer must hold a 100+ °C chamber.
Pick FFF PEEK for chemical-process replacements, lightweight aerospace ducting, semiconductor handling, and spinal/cranial implant prototypes.
Defects and post-processing
The dominant defect is poor crystallinity from inadequate chamber temperature. As-printed PEEK is largely amorphous (~10 % crystalline) and weak; annealing at 150 °C develops the semi-crystalline structure that gives the listed strength.
Layer adhesion is the other risk — Z-direction strength sits at ~60 % of XY. Orient critical loads in-plane.
Suggested parameters
Starting recipe on a high-temperature FFF system (Roboze, miniFactory).
- Nozzle: 410 °C
- Bed: 200 °C
- Chamber: 130 °C minimum
- Layer height: 0.2 mm
- Print speed: 30–40 mm/s
- Anneal: 150 °C / 4 h
Frequently asked questions
Can I print PEEK on a desktop FFF printer?
No. Without a heated chamber above 100 °C the part won't crystallize properly and will warp. Use a dedicated high-temp FFF system.
How does FFF PEEK compare to injection-molded PEEK?
Typically 70–85% of injection-molded strength after annealing, with strong Z-direction anisotropy. For most applications the gap is acceptable; for primary-structure parts it isn't.
Sources
- Victrex PEEK 450G datasheet (reference)
- ASTM F2026 — Polyetheretherketone Polymers for Surgical Implants