Professional PEEK CNC Machining Service in China

What is PEEK?

Polyetheretherketone, abbreviated as PEEK, is a linear aromatic polymer compound containing chains in the main chain of the molecule. PEEK is a high-temperature, high-performance thermoplastic special engineering plastic, which has more significant advantages compared with other special engineering plastics.It has good mechanical properties and chemical resistance and flame retardancy, peeling resistance, abrasion resistance, radiation resistance, hydrolysis resistance, and it is not resistant to strong nitric acid and concentrated sulfuric acid. It is light in specific gravity and has good self-lubricating properties. PEEK materials are widely used in high-tech industries such as aviation, machinery, electronics, chemicals, and automobiles. It can manufacture highly demanding mechanical components.

PEEK

PEEK CNC machining：

There are many ways of molding PEEK material, such as injection molding, extrusion molding, blow molding, pressing, machining and so on. PEEK has good mechanical properties and a high melting point, making it suitable for CNC machining and cutting operations, including turning, milling, sawing, and drilling.

1）Turning

Positive geometry inserts with ground edges are recommended for turning. Machined soft jaws or pie jaws should be used when turning thin-walled tubular shapes. 360° chuck pressure is also recommended to avoid deformation and rough turning of the chuck area of the blank to improve roundness. In addition, inner plugs should be used to prevent compression deformation of thin-walled parts.

2）Milling

When milling, the feed rate should be smaller, and the coolant should be sufficient, otherwise the surface of the product will be discolored and yellowed when the cutting heat generated is too large. Try to use a sharp end mill with a large rake angle and good chip removal. Whether the product will be deformed after processing should be fully considered when clamping. The clamping force and the workpiece clamping method should be properly controlled.

3）Sawing

Sawing is the preferred method of cutting PEEK materials. The saw blade should be selected according to material thickness and precision when cutting, and sufficient clearance must be left to reduce heat build-up. Coolant is indispensable during operation.

4）Drilling

It is not possible to drill directly with a large drill bit. First, use a drill bit with a diameter of less than 10mm to drill the hole, then use a smaller boring tool to drill the hole, and finally use a large boring tool to drill the hole. When drilling, it is necessary to repeatedly withdraw the drill bit to remove chips, and to ensure that the cutting fluid is cooled sufficiently and timely. The drilling feed rate should be appropriately reduced, and the drill bit should be reground in time when the drill bit is worn.

PEEK CNC Machining

Matters needing attention in PEEK CNC machining:

1) Pay attention to control the deformation of the clamp.

2) Pay attention to the stress deformation caused by cutting heat.

3) Pay attention to control glitches.

4) The heat dissipation of plastic is slower than that of metal, and local overheating should be avoided.

5) The thermal expansion coefficient of engineering plastics is larger than that of metals, so when the machining allowance is large, the possibility of deformation due to the elimination of internal stress is also high. When the amount of material removed is relatively large, the blank allowance should be controlled, and symmetrical processing should be used to offset the stress and deformation caused by processing.

6) Excessive amount of cutting tool during processing, insufficient cooling, too fast feed rate, wear and tear of the cutting edge of the drill bit during drilling and not grinding the drill bit in time, excessive cutting heat and cutting force will cause the PEEK material to burst. In the process of machining, each factor should be strictly controlled to avoid bursting.

PEEK CNC Machining Skills:

1) Anneal the PEEK plastic before processing.

2) Use carbide and polycrystalline tools.

3) Use coolant reasonably.

4) Use the correct machining parameters.

5) Avoid contamination.

The advantages and disadvantages of PEEK CNC machining:

Advantages

The advantages of PEEK materials:

1) High temperature resistance. The long-term service temperature of PEEK is 260°C, and the heat distortion temperature of PEEK reinforced grade is as high as 315°C.

2) Superior chemical resistance and hydrolysis resistance. In addition to strong oxidizing acids, PEEK is resistant to various acid solutions in a wide range of temperature and concentration. PEEK can be used in almost all solvents over a wide range of temperatures and concentrations.

3) Excellent mechanical properties, high tensile, high compressive and impact strength. Excellent mechanical properties are still maintained at high temperatures.

4) Good wear resistance properties.

5) Lubrication-free characteristics under high pressure.

6) Great resistance to high-energy radiation.

7) Good dimensional stability.

The advantages of PEEK CNC machining technology:

1) High accuracy.

2) High repeatability.

3) Tight tolerances.

4) Relatively high melting point allows for faster feeding and velocity.

Disadvantages

1) Special handling is required to minimize internal stress and heat-related cracks.

2) Annealing is required.

3) The heat dissipation is not good.

4) It is easy to deform and burst during machining.

The applications of PEEK CNC machining:

Applications of industrial grade PEEK:

Industrial-grade PEEK is a strong, flame-retardant and wear-resistant thermoplastic with high impact strength and low coefficient of friction. It is known for its mechanical properties, even at high temperatures. This grade of PEEK is most commonly used in the aerospace, automotive, chemical, electronics, petroleum, and food and beverage industries.

Applications of Medical Grade PEEK :

Medical-grade PEEK has all the mechanical properties of industrial-grade PEEK. However, in addition to all these properties, medical-grade PEEK materials are chemically resistant and biocompatible, meaning they have no harmful effects on the human body. This makes them especially useful in custom medical implants such as joints.