3D Printing Filament: PEEK

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Polyetheretherketone, better known as PEEK, is known for its exceptional strength, chemical resistance, and ability to withstand extreme environments. PEEK filament is often described as the “gold standard” of thermoplastic filaments.

What Is PEEK Filament?

PEEK (Polyetheretherketone) is a semi-crystalline thermoplastic polymer belonging to the polyaryletherketone (PAEK) family. It was first developed in the 1980s and quickly gained traction in industries such as aerospace, automotive, and medical due to its exceptional mechanical and thermal properties.

When processed into 3D printing filament, PEEK allows engineers, researchers, and manufacturers to create parts that rival those produced by traditional machining or injection molding. PEEK is designed for mission-critical applications where failure is not an option.

Key characteristics of PEEK filament include:

• High melting point

• Excellent chemical resistance

• Superior strength-to-weight ratio

• Biocompatibility (suitable for medical implants in some cases)

Because of these attributes, PEEK is often used as a metal replacement material in demanding environments.

Key Material Properties

Thermal Properties

1. High melting temperature: ~343°C

2. Continuous use temperature: up to 250°C

3. Glass transition temperature (Tg): ~143°C

Chemical Resistance

1. Resistant to hydrocarbons, alcohols, and organic solvents

2. Withstands exposure to acids and bases better than most plastics

3. Low moisture absorption, making it dimensionally stable

Mechanical Strength

1. Tensile strength: ~90–100 MPa

2. High stiffness and rigidity

3. Excellent fatigue resistance, even under cyclic loading

Electrical Properties

1. Low dielectric constant

2. High electrical resistivity

3. Stable insulating properties across a wide temperature range

Biocompatibility

1. Approved for certain medical applications (ISO 10993, USP Class VI)

2. Can be sterilized repeatedly without degradation

Pros and Cons of 3D Printing PEEK Filament

Recommended Printer Settings

Printing with PEEK requires industrial-grade FDM 3D printers capable of maintaining high and stable temperatures. Below are the recommended settings:

Additional Tips:

1. An enclosed heated chamber is essential to prevent warping and ensure crystallinity.

2. Dry the filament before use (PEEK is hygroscopic). Bake at 120°C for 3–4 hours.

3. Use a hardened steel or ruby nozzle to withstand high temperatures.

4. Consider annealing the printed part post-production to improve crystallinity and mechanical strength.

Top Applications for PEEK 3D Prints

Aerospace & Defense

The aerospace sector was one of the earliest adopters of PEEK due to its lightweight yet durable nature:

1. Structural brackets and clamps: Replace aluminum parts while maintaining strength.

2. Cable insulation and housings: PEEK’s electrical resistance ensures safety in avionics.

3. Engine bay components: Withstands high heat and exposure to jet fuel.

4. Interior cabin parts: Flame-retardant and compliant with FAA regulations.

Automotive & Transportation

Modern vehicles demand materials that can handle heat, vibration, and chemical exposure. PEEK is increasingly used in electric vehicles (EVs) and high-performance cars:

1. Gears and bearings: High wear resistance and low friction.

2. Fuel system components: Resistant to gasoline, diesel, and ethanol blends.

3. Under-the-hood parts: Manifolds, seals, and connectors exposed to heat and oil.

4, EV battery housings: Provides insulation and structural integrity.

Medical & Healthcare

PEEK is biocompatible and has been approved for certain long-term implant applications:

1. Spinal cages and orthopedic implants: Lightweight, radiolucent (doesn’t interfere with X-rays or MRI).

2. Dental implants and prosthetics: Strong, durable, and comfortable for patients.

3. Surgical instruments: Can withstand autoclaving without degradation.

4. Custom medical devices: Patient-specific implants and guides.

Industrial Manufacturing

Factories and research labs rely on PEEK for parts that must endure harsh chemicals, high loads, and continuous use:

1. Pump and valve components: Resistant to acids, bases, and solvents.

2. High-performance seals and gaskets: Maintain integrity under pressure.

3. Electrical connectors: Stable insulating properties at high temperatures.

4. Wear-resistant bushings: Long service life in rotating machinery.

Oil, Gas & Energy

Energy exploration and production demand materials that can survive extreme pressure, temperature, and chemical exposure:

1. Downhole tools: Withstand high pressure and corrosive drilling fluids.

2. Seals and insulators: Maintain performance in deep-sea or underground conditions.

3. Compressor components: Handle continuous stress and heat.

Try Hi3DP FDM 3D Printing Service

Looking to skip the calibration and dial-in work?

Hi3DP’s FDM 3D printing service specializes in PLA, PETG, ABS, TPU and other engineering-grade materials. Here’s why thousands of customers trust Hi3DP:

Instant Quotes & Rapid Turnaround: Upload your STL, choose PETG, and get pricing within minutes—shipped in as little as 2 business days.

Quality Assurance: Parts undergo dimensional inspection and strength testing to meet your specifications.

Custom Finishes & Assembly: Post-processing options include sanding, painting, and chemical smoothing. Assembly and kitting services are available for multi-part projects.

Global Shipping & Support: Whether you’re in North America, Europe, or Asia, we deliver reliable quality worldwide.

FAQs

Q: Can PEEK be 3D printed on a regular desktop printer?

A: No. PEEK requires extremely high temperatures—typically 360–400°C for the nozzle and 120–160°C for the heated bed. It also needs a fully enclosed, heated chamber to prevent warping.

Q: Why is PEEK filament so expensive?

A: PEEK is costly due to its complex manufacturing process and premium performance. Prices range from $300 to $500+ per kilogram. Its value lies in its ability to replace metal in demanding applications.

Q: How strong is PEEK compared to metals?

A: PEEK offers a tensile strength of ~90–100 MPa and excellent fatigue resistance. While not as strong as steel, it can replace aluminum in many applications due to its lighter weight and corrosion resistance.

Q: Is PEEK filament biocompatible and safe for medical use?

A: Yes. PEEK is biocompatible and approved for certain implants and surgical instruments. It’s also radiolucent, meaning it doesn’t interfere with X-rays or MRIs, making it ideal for medical imaging.

Q: What’s the difference between PEEK and ULTEM (PEI)?

A: PEEK has higher strength, better chemical resistance, and a higher continuous-use temperature than ULTEM. However, ULTEM is easier to print and more affordable, making it a good alternative for less demanding applications.

Q: Do PEEK parts need post-processing like annealing?

A: Yes. Annealing improves crystallinity, mechanical strength, and dimensional stability. It’s recommended for critical parts, especially those exposed to heat or mechanical stress.