PEEK Materials for Aerospace Applications: Material Properties, Typical Components and Recommended Grades

Stringent Requirements for Materials in Aerospace

Aircraft need to operate stably under extreme high and low temperatures. Their components must withstand long-term vibration and fatigue, and feature self-extinguishing flame retardancy to guarantee flight safety.

In addition, excellent machinability is essential. Given the complex structure and high precision requirements of aerospace components, traditional materials come with high processing costs and long production cycles, which fail to meet industrial demands. Moreover, lightweighting stands as a core indicator. Reducing aircraft weight can effectively cut fuel consumption and carbon emissions, improve flight performance, and play a vital role in achieving the sustainable development goals of the aviation industry.

PEEK: A Game-Changer for Aerospace Applications

PEEK maintains stable performance across a wide temperature range. It works reliably at -40°C, with a melting point of 343°C and a long-term service temperature up to 260°C, enabling it to adapt to low temperatures at high altitudes and high-temperature environments around aero-engines.

PEEK boasts remarkable resistance to fatigue and creep. It allows components to operate steadily for extended periods during flight and retains superior mechanical properties even under high cyclic fatigue loads.

PEEK features exceptional flame retardancy and self-extinguishing performance, rated UL94 V-0. It produces minimal smoke and toxic gases during combustion, providing solid safety assurance for aircraft interiors.

Machinability is another major advantage of PEEK. Aircraft components demand rigorous precision and complex geometries. PEEK can be processed via injection molding, extrusion, cutting and other forming methods, which facilitates the production of complex, high-precision parts, cuts production costs and boosts manufacturing efficiency.

With a density of merely 1.3 g/cm³, PEEK delivers outstanding specific strength. It is also resistant to salt spray, corrosion and hydrolysis. The material facilitates aircraft lightweighting, achieving dual gains of energy conservation, emission reduction and performance improvement. Gradually, it has become an ideal alternative to traditional metallic materials in aerospace, leading the trend of green and efficient flight.

Core Applications of PEEK in Aerospace

Radar Radomes：PEEK-made radar radomes feature high dimensional accuracy, excellent weather resistance, high strength, light weight, chemical inertness and superior flame retardancy. They ensure stable signal transmission under extreme temperatures.

Fasteners：

Bolts, brackets and other fasteners made of PEEK achieve weight reduction and better fatigue resistance compared with conventional materials. They help cut aircraft weight and improve fuel efficiency. The material resists aviation fuel, hydraulic fluid, de-icing solutions, pesticides, cleaning agents, fire extinguishing chemicals, water, salt and steam. With a UL94 V-0 flame rating, it generates low smoke and low toxic gas emissions.

Wheel Hub Covers：PEEK aircraft wheel hub covers are lightweight, high-strength, easy to transport, reliable and eco-friendly. They protect disassembled wheel hubs during aircraft maintenance and long-distance transportation to avoid damage.

High-voltage Cables & Conduits：PEEK insulated wires feature prominent resistance to high and low temperatures, flame retardancy, radiation resistance and good mechanical properties, making them ideal ultra-high temperature wires for aviation with long service life and resistance to aviation fuel and hydraulic fluid. PEEK conduits have stable dimensions, excellent creep resistance, fatigue resistance and moisture resistance. They show outstanding anti-aging performance at high temperatures with no obvious drop in tensile strength.

PEEK Cable Ties：Used for bundling and fixing cables to aircraft fuselages. The low moisture absorption of PEEK ensures stable dimensions of cable ties, preventing expansion and damage to wire insulation.

Aero-engine Components：Lightweight composite materials have become the standard for new aircraft development. PEEK is used to manufacture lightweight fastening systems, bolts, nuts, inserts and brackets for aero-engines. Its wear resistance and creep resistance reduce maintenance frequency effectively.

Recommended PEEK Products of Joinature (Partial List)

Requirements for Structural Mechanical Properties-Glass Fiber (GL) & Carbon Fiber (CA) Reinforced Series,Suitable for scenarios requiring high strength, high rigidity, creep resistance and lightweighting (density: 1.3 g/cm³).

Requirements for Insulating & Thin-Wall Components-Pure Resin Granules (G Series)