PEEK is an extremely strong, durable, mechanically and chemically resistant material. PEEK is often compared with aluminum alloys, but PEEK is lighter than aluminum, making it the perfect candidate for lightweight and strong applications.
Quick jump to:
- What is PEEK?
- Properties and applications
- Applications per industry
- Print settings
- Post processing
- PEEK 3D printers
- PEEK filaments
What is PEEK?
Polyether Ether Ketone or PEEK is a semi crystalline polymer(organic) developed in the 1980s. PEEK is formed by the step-growth polymerization by the dialkylation of bisphenolate salts. 3D printing PEEK is a good alternative to traditional metal manufacturing techniques when you deal with low-volume production and complex designs that demand exceptional mechanical en chemical resistance.
PEEK properties and applications
PEEK has exceptionally high mechanical, thermal, and chemical resistant properties that are maintained at high temperatures. An object made of PEEK becomes ‘rubbery’ from a temperature of around 140°C. This is the Glass Transition Temperature. From 200°C it starts losing its chemically resistance to Chlorine/Bromide, Fluorine, HF and HBr, concentrated Sulphur, Nitric acids, Ketones and Nitrobenzene. PEEK is elastic and has a high tensile modulus, making PEEK ideal for high stress applications. Think of piston parts, bearing casings and so on. The above described properties make it the ideal choice for aerospace, oil and gas and automotive industries.
In addition, PEEK is water resistant and easy to sterilize which is why it’s also widely used in the medical industry. PEEK filament is one of the most expensive filaments on the market. The high cost of the raw material, relatively low demand and various patents are a few of the reasons that affect the price of this versatile 3D printing material.
PEEK applications per industry
Aerospace and aviation
- Engine parts
- Contact material for tribological interaction
- Exterior parts of aircrafts
- Intricate tubing material for wire protection
Medical and healthcare
- Handles of dental syringes
- Sterile boxes
- Load bearing implants
Electrical / electronic
- Used as electrical components for long-term operating conditions
- During the handling of silicon wafers PEEK components minimize contamination and maximize safety
- Used in soldering process
- Piston units
- Bearing casings
PEEK print settings
PEEK is difficult to print. You need a industrial 3D printer with a high temp extruder and high temp heated bed. Additionally it needs to have a closed and temperature controlled print chamber due to the fact that PEEK is very sensitive to temperature fluctuation.
You need high quality equipment because the processing conditions used to print PEEK can influence the crystallinity and hence the mechanical properties. If a part has a brown discoloration as opposed to a beige color, it could identify the problem of improper crystallization.
General print settings
- Extruder temperature: 375°C – 410°C
- Print bed temperature: 130°C – 145°C
- Print chamber temperature: 70°C – 150°C
- Print speed: 10 – 50 mm/s (the lower the better)
Annealing a printed part in an oven de-stresses the part and improves its mechanical properties. Use a hot air oven but don’t preheat. Both the part as well as the oven should be at room temperature when you start annealing. Raise the temperature of the oven to 150°C for one hour. Then raise the temperature to 200°C for another hour. Reduce the temperature to 150°C for thirty minutes. Then let the part slowly cool until it has reached room temperature again.