PEEK Material Properties Overview

Physical Properties

Density: Typically ranges from 1.26–1.72 g/cm³ depending on grade and additives. Pure PEEK resin generally has a density of 1.32 g/cm³ or 1.42 g/cm³.
Water Absorption: Very low. At 23°C, the saturated water absorption is around 0.10%–0.50%. At 25°C for 24 hours, water absorption is usually about 0.15%, indicating excellent water stability.
Thermal Conductivity: Low, around 0.25 W/(m·K). Carbon fiber-reinforced grades have 3.5x higher conductivity than unfilled PEEK.
Specific Heat Capacity: Approximately 2.20 J/g·°C, indicating good thermal absorption or dissipation capability during temperature changes.

Tensile Strength: Generally between 90.0–250 MPa. For instance, PEEK5600G has 90 MPa at 23°C, while PEEK5600CF30 reaches up to 210 MPa.
Flexural Strength: Typically ranges from 100–145 MPa. PEEK5600GF30 can reach 212 MPa at 23°C.
Flexural Modulus: Around 3.8 GPa, indicating high rigidity.
Impact Strength: Charpy impact strength and Izod impact strength are 6.4 ft-lb/in and 1.18 ft-lb/in respectively. Unnotched PEEK5600G shows no breakage under impact.
Wear Resistance: Maintains excellent wear resistance even at 250°C. With PTFE, graphite, and carbon fiber fillers (e.g., PEEK5600LF30), the coefficient of friction can be as low as 0.18.

Glass Transition Temperature (Tg): Around 143°C, contributing to good toughness and processability at low temperatures.
Melting Point: Generally around 334°C; some references cite 343°C, demonstrating excellent thermal stability.
Continuous Use Temperature: Up to 260°C with stable mechanical performance.
Heat Deflection Temperature: Typically 200–260°C. With 30% glass fiber or carbon fiber reinforcement, it can reach up to 315°C.

Corrosion Resistance: Excellent resistance to acids, bases, solvents, and fuels. Not resistant to concentrated sulfuric acid.
Hydrolysis Resistance: Outstanding resistance in hot water and steam environments—suitable for long-term use.
Self-Lubrication: Offers excellent self-lubricating properties, ideal for applications requiring low friction and wear.
Flame Resistance: Achieves UL94 V-0 rating without any flame retardants. Emits low smoke and toxicity under flame conditions.

Dielectric Constant: Around 3.2; remains stable over a wide frequency range.
Dielectric Loss: Low loss factor (~0.002), making it ideal for high-frequency insulation.
Dielectric Strength: Around 20 kV/mm; excellent insulation under high voltage.
Surface Resistivity: Ranges from 10¹⁴ to 10¹⁶ ohm/square.

Other Characteristics

Dimensional Stability: Maintains excellent dimensional integrity under both high and low temperatures.
Machinability: Supports injection molding, extrusion, turning, milling, drilling, tapping, bonding, and ultrasonic welding.
Biocompatibility: Non-irritating to human tissue and suitable for implants; its density and modulus are similar to human bone.
Radiation Resistance: Highly resistant to high-dose gamma radiation—suitable for nuclear applications.