PEEK Material Properties

Polyetheretherketone, commonly referred to as PEEK is an organic, high performance engineering thermoplastic polymer. PEEK offers excellent wear and abrasion resistance, best-in-class fatigue resistance, and ease of melt processing. It has superior strength-to-wear ratio, providing excellent mechanical strength and dimensional stability. PEEK is considerable stronger and stiffer than most polymers, but softer than metal.

PEEK performs over a wide range of temperatures and can be use continuously in operating temperatures up to 250°C. Excellent chemical resistance to organics, acids, and bases. It does not undergo hydrolysis and can be used for thousands of hours in steam or high-pressure water without significant property degradation. PEEK has been tested at the highest flame retardance level and has very low smoke and toxic gas emissions when exposed to flames.

PEEK has excellent sliding characteristics, especially in the bearing field. Its own sliding properties greatly reduce the coefficient of friction, allowing certain parts to operate without lubricants and also in media such as water, weak acids, and alkalis.

The four most common grades of PEEK are unfilled, 30% carbon filled, 30% glass filled, and 20% PTFE and graphite filled.

Applications: Wear rings, bearings, fasteners, flat washers, seals, and various applications in the healthcare, transportation, electronics, and aerospace industries.

PEEK, polyethetherketone (unfilled, typical values)

Appearance Tan, Black
Density 1.30 g/cm3
Water absorption (24 hr) 0.10%
Wear Rate 28 µm/km
Dynamic Coefficient of Friction 0.3 – 0.5
Hardness, Rockwell M 105
Tensile Modulus of Elasticity 4000 MPa
Tensile Strength 115 MPa
Flexural Strength 160 MPa
Flexural Modulus 3700 MPa
Compressive Strength 118 MPa
Shear Strength 55 MPa
Poisson’s Ratio 0.33
Thermal Conductivity 0.24 W/m/K
Specific Heat 200°C 2150 J/kg/°C
Glass Transition Temperature 150°C
Surface resistivity 1.9E+17 ohm
Dielectric Strength 3.00 mm 15/k/mm
Dielectric Constant 1 MHz 3.05
Flame Rating 1.6 mm V-0