PEEK Material Overview: Properties, Grades, Applications, and Extruded Shapes

What Is PEEK?

Polyetheretherketone (PEEK) is one of the most widely used materials within the polyaryletherketone (PAEK) family of high-performance thermoplastics. Since its commercial introduction in the early 1980s, PEEK has become a preferred engineering material for demanding applications in the aerospace, oil and gas, semiconductor, medical, automotive, electronics, and chemical processing industries.

PEEK is often selected when performance is more important than material cost. It combines exceptional mechanical strength, chemical resistance, dimensional stability, and high-temperature performance with the ability to be melt processed using conventional thermoplastic manufacturing methods such as extrusion and injection molding.

Compared to lower-performance engineering plastics, PEEK maintains its properties at significantly higher temperatures while offering excellent resistance to aggressive chemicals, steam, and hydrolysis. It is also frequently specified as a stronger alternative to fluoropolymers such as PTFE, PVDF, and PCTFE in applications requiring improved structural performance.

Key Properties of PEEK

High Temperature Resistance

One of PEEK’s defining characteristics is its ability to operate continuously at elevated temperatures. With a glass transition temperature (Tg) near 300°F and a melting temperature around 650°F, PEEK performs well beyond the limits of many traditional engineering plastics.

Tg~300º

This high thermal capability allows PEEK components to maintain strength and dimensional stability in environments involving hot fluids, steam sterilization, or continuous thermal cycling.

Excellent Chemical Resistance

PEEK demonstrates outstanding resistance to a broad range of chemicals including:

• Hydrocarbons 

• Organic solvents 

• Acids and bases 

• Hot water and steam 

• Automotive and aerospace fluids 

This chemical resistance makes PEEK suitable for aggressive operating environments where many engineering plastics would degrade or swell.

Mechanical Strength and Wear Resistance

PEEK offers an exceptional balance of:

• Tensile strength 

• Stiffness 

• Impact resistance 

• Fatigue resistance 

• Creep resistance 

• Wear performance 

Reinforced and bearing grades further improve stiffness, dimensional stability, and tribological performance for dynamic applications such as bushings, seals, thrust washers, and compressor components.

Processing and Manufacturing of PEEK Shapes

PEEK can be processed using several manufacturing methods including:

• Extrusion 

• Injection molding 

• Compression molding 

• Thermoforming 

• Machining from stock shapes 

Because of its high processing temperatures, specialized extrusion and molding equipment is typically required to achieve optimal material performance and minimize resin degradation.

For machinable plastic applications, PEEK is commonly supplied in stock shapes such as:

• Rod 

• Plate 

• Sheet 

• Tube 

• Custom extruded profiles 

Custom extruded PEEK shapes can significantly improve machining yield and reduce material waste compared to machining from oversized stock forms.

Growth of the PEEK Market

The global demand for PEEK continues to grow as industries seek lighter, stronger, and more chemically resistant alternatives to metals and conventional plastics. Over the past decade, annual growth rates for PEEK materials have generally been estimated in the 6–8% range.

Applications involving electrification, semiconductor manufacturing, medical devices, aerospace lightweighting, and industrial automation continue to drive increased use of PEEK-based materials worldwide.

Understanding PEEK Resin Grades

Although many manufacturers market proprietary trade names for extruded shapes and semi-finished stock, the underlying polymer chemistry remains fundamentally the same.

All PEEK materials are based on polyetheretherketone chemistry, and the baseline properties are primarily determined by the resin itself. The quality of the final shape or molded component depends heavily on proper processing techniques that preserve the inherent properties of the polymer.

Poor processing conditions can negatively affect mechanical properties, dimensional stability, color consistency, and long-term performance.

Major PEEK Resin Manufacturers

Today, most commercial PEEK resins are supplied by:

• Victrex 

• Syensqo (formerly Solvay) 

• Evonik 

These suppliers produce unfilled, reinforced, wear-resistant, and specialty PEEK compounds for demanding engineering applications.Additional manufacturers, including emerging suppliers in Asia, continue to enter the market as global demand increases.

Common PEEK Resin Grades

Victrex PEEK Grades

• Victrex 150G — Low viscosity grade primarily used for injection molding 

• Victrex 450G — High viscosity grade commonly used for extrusion and thick-wall parts 

• Victrex 450GL30 — 30% glass fiber reinforced 

• Victrex 450CA30 — 30% carbon fiber reinforced 

• Victrex 450FC30 — Bearing grade with carbon fiber, graphite, and PTFE additives 

• Victrex HT — Higher temperature PEK-based material 

Syensqo Ketaspire PEEK Grades

• Ketaspire KT-880 — Low viscosity injection molding grade 

• Ketaspire KT-820 — High viscosity extrusion grade 

• Ketaspire KT-820 GF30 — Glass fiber reinforced 

• Ketaspire KT-820 CF30 — Carbon fiber reinforced 

• Ketaspire KT-820 SL30 — Wear-resistant bearing grade 

• Ketaspire PEEK XT — Higher temperature PEEK formulation 

Evonik Vestakeep Grades

• Vestakeep 1000–3000 — Lower viscosity molding grades 

• Vestakeep 4000 — High viscosity extrusion grade 

• Vestakeep 5000 — Highest viscosity grade with improved toughness 

• Vestakeep 4000GF30 — Glass fiber reinforced 

• Vestakeep 4000CF30 — Carbon fiber reinforced 

• Vestakeep 4000FC30 — Wear-resistant bearing grade 

Reinforced and Bearing Grades of PEEK

Glass and carbon fiber reinforced PEEK grades are commonly used when additional stiffness, strength, or dimensional stability is required.

Popular reinforced formulations include:

• 30% glass fiber reinforced PEEK 

• 30% carbon fiber reinforced PEEK 

• 10-10-10 bearing grade PEEK 

The “10-10-10” bearing grade typically contains:

• 10% carbon fiber 

• 10% graphite 

• 10% PTFE 

These additives improve wear resistance, reduce friction, and enhance performance in dynamic sealing and bearing applications.

As a semicrystalline polymer, reinforcement also increases heat deflection performance, allowing reinforced PEEK grades to operate under load at temperatures exceeding the glass transition temperature.

Specialty PEEK Materials

In addition to standard natural and reinforced grades, PEEK is also available in:

• ESD-safe grades 

• Metal detectable grades 

• FDA-compliant grades 

• Medical implant grades 

• Colored compounds 

• Reprocessed and recycled formulations 

Recycled PEEK materials are increasingly used in applications where sustainability goals or material cost reduction are important considerations.

Common Applications for PEEK

PEEK is used across a wide range of industries and applications including:

Aerospace

• Structural brackets 

• Wire and cable components 

• Bearings and bushings 

• Lightweight replacement for metal parts 

Oil and Gas

• Downhole seals 

• Compressor components 

• Backup rings 

• Valve seats and bearing components 

Medical Devices

• Spinal fusion cages 

• Orthopedic implants 

• Dental implant components 

• Sterilizable surgical instruments 

Semiconductor and Electronics

• Wafer handling components 

• Electrical insulators 

• High-temperature connectors 

• Precision machined manifolds 

Food and Packaging Equipment

• Hot-fill valve components 

• Wear strips 

• Bearings and rollers 

• Chemical-resistant seals 

Automotive and Electrification

• EV battery components 

• High-temperature connectors 

• Wear-resistant thrust washers 

• Lightweight structural parts 

Today, PEEK can be found in aircraft systems, semiconductor equipment, medical implants, industrial automation equipment, and consumer electronics around the world.

Extruded PEEK Shapes for Machined Parts

Extruded PEEK stock shapes remain a critical material solution for precision machined plastic components.

Common extruded forms include:

• PEEK rod 

• PEEK plate 

• PEEK sheet 

• PEEK tube 

• Custom extruded profiles 

For high-cost materials such as PEEK, near-net extruded shapes can dramatically reduce machining waste and improve overall material utilization.

Manufacturers specializing in precision extrusion of high-performance polymers can also provide custom geometries tailored to specific machining requirements and end-use applications.

Why Engineers Specify PEEK

Engineers and designers continue to specify PEEK because it offers a unique combination of:

• High temperature capability 

• Chemical resistance 

• Mechanical strength 

• Wear resistance 

• Hydrolysis resistance 

• Lightweight performance 

• Dimensional stability 

• Long-term reliability 

Few thermoplastics can match the overall balance of performance offered by PEEK in extreme operating environments.

Need Custom Extruded PEEK Shapes?

Companies specializing in high-performance plastic extrusion can supply custom PEEK rod, tube, sheet, plate, and profile shapes engineered for demanding industrial applications.

Custom extrusion capabilities can help reduce machining cost, improve material yield, and support highly specialized component designs across aerospace, medical, semiconductor, energy, and industrial markets.