CNC Machining Materials

PEEK

At a glance

Processes

CNC Mill
CNC Lathe

Lead Time

As fast as 2 days

Colors

Opaque beige

Tolerance

With drawing: as low as +/- 0.005 mm
No drawing: ISO 2768 medium

Price

$$$

Applications

Metal-alternative for high-stress applications

Grades

Standard PEEK, 30% Glass Filled

About the material

In high-stress/high-temperature applications, PEEK is a great lightweight substitute for most soft metals. Additionally, PEEK is resistant to moisture, wear, and chemicals.

Glass-filled PEEK is a high performance plastic with excellent rigidity, strength and toughness. The addition of glass fibers enhances its ability to maintain dimensional stability even in harsh thermal and chemical environments. This material is often used in the following industries: aircraft, automotive, medical, chemical, semiconductor and microwave.

Material Properties

PEEK

Yield Strength (tensile)

14,000 psi

Elongation at Break

20%

Hardness

Rockwell R125

Density

0.047 lbs / cu. in.

Maximum Temp

480° F

McMaster Part Number

8504K811

PEEK (30% Glass Filled)

Yield Strength (tensile)

14,000 psi

Elongation at Break

3%

Hardness

Rockwell R126

Density

0.054 lbs / cu. in.

Maximum Temp

480° F

McMaster Part Number

8678k14

Material Finish

PEEK comes in an opaque beige color and can be machined to a variety of surface finishes.

Design Recommendations

Min Wall Thickness

0.5 mm

Min End Mill Size

0.8 mm (0.03 in)

Min Drill Size

0.5 mm (0.02 in)

Max Part Size

1200 x 500 x 152 mm [x,y,z] (mill)
152 x 394 mm [d,h] (lathe)

Undercuts

Square profile, full radius, dovetail profiles

Radii : Depth

Depth must not exceed 12x drill bit diameter.
For end mills, depth must not exceed 10x tool diameter.

Cost Saving Tip

To reduce costs, limit the number of part setups, the number of inspection dimensions or tight tolerances, and deep pockets with small radii.

PEEK FAQs

Is PEEK machinable?

Yes, PEEK (polyetheretherketone) can be machined to a variety of surface finishes. In high-stress/high-temperature applications, PEEK is a great lightweight substitute for most soft metals. It’s resistant to moisture, wear, and chemicals

Can PEEK be 3D printed?

PEEK can be 3D printed. Its unique properties allow for the creation of almost any complex geometry, some of which cannot be manufactured using other technologies. The slower the 3D printing speed, the more accurate the end result.

What is the melting point of PEEK?

PEEK has a melting point around 341°C (646°F). It has the ability to maintain stiffness and can be used continuously in temperatures up to 260°C (480°F). It can also be used in hot water or steam without compromising physical properties.

What is PEEK plastic used for?

PEEK is often used in the following industries: aircraft, automotive, medical, chemical, semiconductor and microwave to manufacture items used in demanding environments, including pumps, bearings, HPLC columns, compressor plate valves, cable insulation, and piston parts.

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