CNC Machining PEEK: Types, Properties, Application & Tips
PEEK stands for Polyether Ether Ketone and is a thermoplastic used widely across various applications in the electrical and medical industry. PEEK offers excellent mechanical properties and is also highly corrosion-resistant. If you are inclined to learn more about CNC machining PEEK this guide below can be of great help, so let's delve in.
What is PEEK (polyether ether ketone)?
Polyether Ether Ketone is a thermoplastic also called PEEK. It is an engineering plastic that has a semi-crystalline structure and offers high performance in multiple applications. It offers excellent properties like wear resistance, chemical resistance, abrasion, and water resistance and has seamless mechanical properties.
PEEK plastics also can retain their properties when subjected to high temperatures. They have a high melting point and can be easily exposed to steam and hot water. The PEEK plastic occurs in various forms of bar form which is suitable for CNC machining, granular form, and filaments.
Types of PEEK Plastic Material
There are different types of PEEK plastics and each type comprises unique properties and suitability for certain applications. Some of these types of PEEK plastic are mentioned below:
PEEK 1000
PEEK 1000 is made using 100% pure PEEK resin, it is suitable for applications that need a high impact resistance like tough applications. This type of PEEK is quite effective for the process of sterilization due to its ability to handle high pressure and temperature from different sterilization techniques.
PEEK 1000 also meets the US and EU requirements of the FDA and is also used in the food processing and health industry.
PEEK HPV
PEEK HPV comprises some addition of carbon fiber, graphite, and PTFE which makes it a plastic with bearing-grade. It has a high resistance against wear and also low friction. This type of PEEK also offers a high peak pressure and is suitable for applications consisting of a friction interface.
PEEK CA30
PEEK CA30 has 30% carbon fiber and it offers good mechanical strength, creep resistance, and elasticity. It also offers high thermal conductivity and offers quick heat dispersion from the bearing surface. It is used in aerospace, automobile, and oil and gas industries for its high temperature and impact resistance followed by low friction.
PEEK GF30
PEEK GF30 has 30% glass fiber, offers creep resistance, and has rigidity followed by improved dimensional stability which makes it suitable for the structural parts. It can withstand loads when subjected to high temperatures. It is also used as a sliding part.
Properties of PEEK
PEEK machining is opted for different applications due to the excellent properties it comprises, and some of these properties are as follows:
High Resistance
PEEK is a highly resistant material, it offers resistance against chemicals that are corrosive. PEEK material has the same resistance as offered by nickel steel. It can maintain its structure even at high temperatures with non-corrosive chemicals and dissolves only in concentrated sulphuric acid.
It also offers an exemplary performance on high frequencies and temperatures. It has a stable structure and even when operated under a high dose of ionization resistance it can maintain its stability. PEEK offers high melting point and durability which ensures that it does not deform even when subjected to high temperature.
High Rate of Workability
PEEK has high workability especially when subject to CNC machining. It has an excellent processing capability and can be processed with different methods quite conveniently. Apart from CNC machining, PEEK can also be processed through melt spinning, injection molding, and extrusion molding. It is known for its self-extinguishing properties during combustion and produces a negligible amount of gas and smoke.
Seamless Mechanical Properties
PEEK has high-temperature resistance due to which it can retain its size when subjected to high temperature. It also has excellent creep resistance which makes it suitable to withstand pressure during the machining process. It also has a high wear resistance and low friction coefficient which makes it suitable for diverse industrial applications.
Low Absorption Rate
PEEK material can even retain its structure when subjected to wet areas. It offers hydrolysis resistance and hence is suitable in wet environments. It can also operate very well under extreme ionization radiation and gamma radiation.
Advantages of CNC Machining PEEK
There are multiple advantages offered by CNC machining PEEK and due to these benefits, it is considered to be a suitable process for manufacturing custom PEEK parts. Some of these advantages are as follows:
Highly Precise and Accurate: The process of CNC machining PEEK offers high accuracy and precision which is very important for manufacturing components that have complex geometries and require tight tolerance. Industries like medical, electronics, and aerospace require such accurate parts.
Excellent Surface Finishing: PEEK CNC machining offers an excellent surface which helps to reduce the need for having any post-processing for surface finishing and hence the quality of the components is quite enhanced.
Repeatability and Consistency: Usinage CNC is a process suitable for manufacturing consistent components in batches one after the other. It helps manufacture parts that are equipped with identical properties and shapes and therefore it is suitable for producing components in mass volume
Preserved Material Properties: CNC machining preserves the properties of PEEK after machining. PEEK offers chemical resistance, high strength, and thermal stability and the machined parts have all these properties retained after going through the process.
Rapid Processing: CNC machining offers rapid prototyping and quick turnaround times when compared to other processes. Similarly, the PEEK components can also be manufactured quickly using CNC machining which is very important for such projects where time constraints prevail.
Flexibility in Tooling: CNC machines are easy to reprogram and accommodate different specifications for parts and designs. Such flexibility offered by CNC machining PEEK allows catering to small batch manufacturing by having new tools for new production runs.
Diverse Processing: The PEEK components which have complex geometries and shapes and comprise intricate designs may easily be manufactured through the CNC machining process. It is a versatile process that caters to specialized applications.
Applications of PEEK CNC Machining
PEEK machining is compatible with various applications some of which are given below:
Pétrole et gaz
In the oil and gas sector, harsh conditions are prevalent like aggressive chemicals and high temperatures where other materials may fail. Whereas the PEEK machined components work very well due to their chemical resistance properties and also they can tolerate heat. PEEK valves are used in the oil and gas industry for their exceptional durability.
Aérospatiale
Aircraft require components that can withstand extreme conditions and are also light in weight. PEEK is used to manufacture insulation of the aircraft and the cable sheaths. The lightweight structure of PEEK machined components offers fuel efficiency and due to being heat resistant, it offers durability.
Médical
In the medical industry, PEEK is mostly used in orthopedics as it plays a role in spinal implant creation to deal with degenerative disc issues. The damaged discs are substituted with the PEEK cages and due to its biocompatibility, it helps to prevent adverse reactions and also offers flexibility and support.
Automobile
The automobile industry always requires materials that help to reduce the weight of a vehicle and enhance fuel efficiency. PEEK components like seal rings, thrust washers, and gears are lightweight, wear-resistant, and also offer low friction, being suitable for the pressure and stress an automobile may pass through.
CNC Machining PEEK Tips
To attain the most functional and high-performing PEEK components, some of the important CNC machining PEEK tips you can follow are given below:
- Recuit PEEK offers to reduce the chances of deformation on the PEEK rods when passed through stress during machining.
- The use of silicon carbide cutting tools helps to cut PEEK in a very refined way, however, if the PEEK comprises carbon fiber and tight tolerance is needed, diamond tools must be used.
- PEEK needs to be cooled down during the machining process so that any breakage can be prevented. PEEK doesn't have the ability to dissipate heat on its own and hence requires a liquid coolant.
- PEEK has low elongation compared to the other types of plastics, therefore, deep-hole drilling should be avoided.
Conclusion
PEEK is a very commonly used plastic in diverse applications and understanding its types, advantages, and essential tips for machining may help in manufacturing and choosing PEEK components.
As you have already gone through the guide above you must have learned a lot of important aspects of PEEK and if you wish to have customized PEEK components, you can contact DEK. We design and manufacture flexible, robust, and affordable custom PEEK components for your projects.
FAQ
Is PEEK Easy to Machine?
PEEK machining is not very easy because the part must be prepared before machining to achieve some ease.
Why is PEEK Plastic So Expensive?
PEEK plastic is expensive because of its complex process of manufacturing and its properties like chemical resistance, mechanical strength, and thermal stability.
