PEEK CF30
Carbon-fiber filled PEEK, a metal replacement
Typical values for the temper in the title
PEEK CF30 contains 30% short carbon fibers. The fibers roughly double the strength (about 210 MPa) and raise the modulus 5–6 times (about 20 GPa), reduce thermal expansion and improve creep and wear resistance, while the material stays light (about 1.4 g/cm³).
It is used for light structural parts replacing aluminum and even steel: aerospace brackets, pump and compressor parts, bearings and gears. The cost: ductility is low (about 2%), and properties depend on fiber orientation.
Mechanical and physical properties
| Property | Value | Note |
|---|---|---|
| Tensile strength Rm | 212 MPa | |
| Elongation A | 2% | |
| Modulus of elasticity E | 20 GPa | |
| Density ρ | 1.41 g/cm³ | |
| Rockwell hardness | R125 | |
| Machinability | 50% | relative rating in the site database |
Structure and family
| Feature | Value | Meaning |
|---|---|---|
| Matrix | PEEK | |
| Filler | 30% short carbon fibers | strength and stiffness |
| Directionality | depends on flow in molding | properties differ along and across the fibers |
Typical values per producer data sheets.
Grades and versions
In engineering polymers, the choice is between an unfilled grade, filled grades (glass or carbon fiber) and special grades (bearing, medical, food). Filler strongly changes strength, stiffness and expansion.
| Version | Properties | When to choose it |
|---|---|---|
| Injection molded | fibers aligned with flow | volume parts |
| Extruded rod and plate | directionality along the rod | machined parts |
Applications
- Light aerospace brackets and structures
- Pump and compressor parts
- Bearings and gears
- Motorsport parts
- Metal replacement in light parts
Fabrication
Machining
The fibers are very abrasive to tools. Diamond (PCD) or coated carbide tools are common. The dust requires extraction.
Joining
Mechanical assembly and bonding after surface treatment.
Directionality
In a part machined from rod, strength along the rod is higher than across it.
Compared with similar materials
| Material | Rm / Rp0.2 | Welding | When it is the better choice |
|---|---|---|---|
| PEEK | 100 MPa | Ultrasonic / Laser | unfilled PEEK: ductile, weaker · material page |
| 6061-T6 | 310 / 276 MPa | Good — ER4043 | aluminum: ductile, twice as heavy · material page |
| PPS | 165 MPa | Ultrasonic | PPS: cheaper, for lower heat · material page |
Common mistakes
Designing to along-fiber strength in every direction
Across the fibers strength is lower.
Machining with HSS tools
The fibers wear them quickly.
Using it in an impact-loaded part
Ductility is low (about 2%).
Equivalents, standards and supply
| ASTM | D8033 |
|---|---|
| Standards | ASTM D8033 |
| Forms | rod · plate |
| Producers | Victrex · Solvay KetaSpire |
Learn more
Values are typical for an unfilled grade (unless stated otherwise) and for comparison only. In polymers, properties depend on grade, filler, temperature, moisture and load duration. For design, rely on the producer data sheet for the specific grade. Sources: ASTM classification standards (D8033, D5205, D5204, D6394, D4067 and others), producer data sheets, and the METAL HUB materials database.
Updated: October 31, 2026