Precision PEEK CNC Machining for High-Performance Parts

Polyether ether ketone (PEEK) is a high-performance thermoplastic known. This engineering plastic is widely used in industries such as aerospace, automotive, medical, and electronics. CNC machining is a subtractive manufacturing process that utilizes computer software to control precision cutting tools. This technology allows for the creation of intricate shapes and features with high accuracy and repeatability. When applied to PEEK, the process yields parts with unparalleled precision and dimensional stability.

Understanding PEEK: A Material of Choice

PEEK is renowned for its exceptional mechanical properties, including high tensile and compressive strength, as well as outstanding fatigue resistance. It operates seamlessly in extreme temperatures, maintaining its properties from -200°C to +260°C. Its chemical resistance is equally impressive, withstanding exposure to a wide range of chemicals, from acids and bases to organic solvents. Furthermore, PEEK exhibits low moisture absorption, excellent electrical insulation properties, and biocompatibility, making it versatile for diverse applications.

PEEK material properties

Tensile Strength	Impact Strength	Tensile Modulus	Heat Deflection	More Information
14,000 PSI	1.55 ft-lbs/in	552,100	285-482° F	Data Sheet

CNC Machining of PEEK

CNC (Computer Numerical Control) machining is a precise manufacturing process that utilizes computer-controlled tools to shape materials. Machining PEEK requires specialized knowledge and techniques due to its unique properties.

Machining Techniques for PEEK

1. Milling

PEEK can be efficiently machined using CNC milling. The use of high-speed steel (HSS) or carbide tools is recommended to maintain tool integrity and precision. Proper coolant and feed rates are essential to prevent overheating, ensuring a high-quality finish and extended tool life.

2. Turning

CNC turning is employed for creating cylindrical parts from PEEK. The cutting speeds should be adjusted to accommodate PEEK’s thermal properties, minimizing tool wear while achieving accurate dimensions. Careful monitoring of feed rates is also important to maintain surface quality.

3. Sawing

Sawing is another effective technique for cutting PEEK into required shapes or sizes. Preheating the material to around 120°C can help improve cutting efficiency. Using appropriate saw blades with suitable clearance and rake angles will enhance the quality of the cut and reduce tool wear.

4. Drilling

Drilling PEEK requires attention to cutting parameters to avoid overheating. Preheating to 120°C is recommended for carbon-fiber-reinforced PEEK. The use of sharp drill bits with the correct clearance and rake angles is crucial to achieving clean holes without damaging the material.

Natural PEEK vs. Carbon-Fiber-Reinforced PEEK

Milling and Turning

Parameter	Natural PEEK	Carbon-Fiber-Reinforced PEEK
Preheat	No preheat necessary	No preheat necessary
Clearance angle (°)	5 to 10	15 to 30
Rake angle (°)	10 to 30	10 to 15
Cutting speed (m/min)	50 to 200	200 to 300
Feed rate (mm/rev)	0.1 to 0.5	0.1 to 0.5

Sawing

Parameter	Natural PEEK	Carbon-Fiber-Reinforced PEEK
Preheat	None	Preheat to 120°C
Clearance angle (°)	15 to 30	15 to 30
Rake angle (°)	0 to 5	10 to 15
Cutting speed (m/min)	500 to 800	200 to 300
Pitch (mm)	3 to 5	3 to 5

Drilling

Parameter	Natural PEEK	Carbon-Fiber-Reinforced PEEK
Preheat	None	Preheat to 120°C
Clearance angle (°)	5 to 10	6
Rake angle (°)	10 to 30	5 to 10
Cutting speed (m/min)	50 to 200	80 to 100
Feed rate (mm/rev)	0.1 to 0.3	0.1 to 0.3

Benefits of PEEK CNC Machining

CNC machining of PEEK (Polyetheretherketone) offers several distinct advantages, making it an ideal choice for high-performance applications across various industries. Here are some of the key benefits:

1. CNC machining ensures tight tolerances and consistent part quality, crucial for applications requiring exact specifications.
2. Capable of producing intricate shapes and designs that would be challenging with traditional manufacturing methods.
3. Reduces waste by precisely cutting PEEK, maximizing material utilization and lowering costs.
4. PEEK’s superior mechanical and thermal properties result in durable, lightweight components suitable for demanding environments.
5. CNC machining can be easily scaled for both small batches and large production runs, offering flexibility to manufacturers.
6. llows for tailored designs to meet specific application requirements, enhancing functionality and performance.
7. Automated processes speed up production times, facilitating quicker turnaround for projects.
8. Achieves high surface finishes and dimensional accuracy, often reducing the need for extensive post-machining work.

Applications of PEEK CNC Machined Parts

PEEK (Polyetheretherketone) is increasingly recognized for its suitability in a wide range of industrial applications due to its outstanding properties. Its exceptional resistance to wear, heat, and radiation, coupled with low flammability and minimal toxic gas emissions, makes it an ideal choice for critical components across various sectors.

Key Industries Utilizing PEEK

1. Automotive: PEEK is used in components like bearings, seals, and thrust washers, where durability and thermal stability are essential for performance under stress and heat.
2. Medical: Its biocompatibility allows for use in surgical instruments and implantable devices, ensuring safety and reliability in medical applications.
3. Electronics: PEEK is employed for cable insulation and components in semiconductor fabrication, benefiting from its excellent electrical properties and thermal stability.
4. Marine: The material’s resistance to corrosion and harsh environments makes it suitable for marine applications, including pumps and valves.
5. Nuclear: PEEK’s ability to withstand radiation and maintain structural integrity makes it valuable in nuclear applications where reliability is critical.
6. Construction: Components such as bearings and seals in construction equipment benefit from PEEK’s wear resistance and longevity.
7. Transportation: Used in parts requiring lightweight and high-performance materials, PEEK contributes to efficiency in various transportation applications.
8. Mining: Components like pumps and seals are designed to endure harsh conditions and abrasive materials.
9. Manufacturing: PEEK’s performance in high-temperature applications makes it ideal for tooling and parts in manufacturing processes.
10. Pharmaceutical: Its chemical resistance allows PEEK to be used in equipment that must withstand aggressive cleaning and sterilization processes.
11. Energy and Power: PEEK parts are used in applications that require resistance to high temperatures and corrosive environments, such as power generation and oil & gas sectors.
12. Aerospace: Components like thrust washers, seals, and other critical parts benefit from PEEK’s lightweight nature and thermal stability.

Example Parts Machined from PEEK

• Bearings
• Thrust washers
• Seals
• Piston parts
• Semiconductor components
• Pumps
• Compressor plate valves
• Cable insulation
• Ultra-high vacuum parts
• Gaskets
• Insulators
• Valve seats
• Wear pads
• Guides
• Spacers

PEEK Machining Methods Comparison

CNC machining offers high accuracy and excellent mechanical performance. It is suitable for a variety of complex parts but may face limitations in geometric intricacy compared to 3D printing.

3D printing is ideal for creating complex and partially hollow geometries, especially in biocompatible medical implants. However, it currently has fewer material options compared to traditional machining and molding methods.

Injection molding is effective for high-volume production, delivering good mechanical performance. It requires specialized equipment due to PEEK’s high melting point, which can be at the upper limits of many injection molding machines.

Process	Complexity of Geometries	Mechanical Performance	Accuracy & Repeatability
CNC Machining	Okay	Good	Good
3D Printing	Good	Okay	Okay
Injection Molding	Good	Good	Good

When choosing a processing method, consider the specific requirements of your project, including time, budget, and desired end product characteristics. Other high-temperature plastics, such as PEKK or Ultem, may also be viable alternatives depending on application needs.

Precision PEEK CNC Machining by BOYI

Are you looking for professionals to handle your next PEEK CNC machining project? BOYI expert team offers advanced CNC machining services, ensuring high precision and quality results. Our skilled technicians are experienced in meeting specific needs, helping you achieve your project goals. Feel free to reach out for more information!