Grades / PEEK CF30
PEEK CF30, the grade that holds a dimension
CF30 is what semiconductor fixtures and wafer handling parts are made of, and not mainly for strength. Carbon fibre brings three properties at once: it holds a dimension, it moves heat out of the part, and it bleeds off static charge. That last one also rules it out of any part that has to insulate.
PEEK CF30 against the other grades
Typical published values. The full matrix, with what each row changes, is on the property data page.
| Property | Unit | PEEK CF30 | Unfilled | GF30 | CF30 | Bearing |
|---|---|---|---|---|---|---|
| Density | g/cm³ | 1.40 - 1.44 | 1.30 - 1.32 | 1.49 - 1.51 | 1.40 - 1.44 | 1.44 - 1.46 |
| Tensile strength | MPa | 130 - 140 | 90 - 100 | 150 - 170 | 130 - 140 | 90 - 110 |
| Tensile modulus | GPa | 12 - 14 | 3.5 - 4.0 | 9 - 11 | 12 - 14 | 7 - 9 |
| Coefficient of friction, dry against steel | µ | 0.20 - 0.30 | 0.30 - 0.40 | 0.35 - 0.45 | 0.20 - 0.30 | 0.10 - 0.20 |
| Thermal expansion, below Tg | µm/m·K | 14 - 18 | 45 - 50 | 20 - 24 | 14 - 18 | 18 - 24 |
| Thermal conductivity | W/m·K | 0.85 - 0.95 | 0.25 | 0.40 - 0.45 | 0.85 - 0.95 | 0.6 - 0.9 |
| Volume resistivity | Ω·cm | 10³ - 10⁶ | > 10¹⁵ | > 10¹⁵ | 10³ - 10⁶ | 10³ - 10⁶ |
| Tolerance a shop quotes | mm | ±0.025 | ±0.05 | ±0.05 | ±0.025 | ±0.05 |
Choose it when
- Dimensional stabilityExpansion around 14 to 18 µm/m·K, close to stainless steel and about a third of unfilled PEEK.
- Static dissipationVolume resistivity in the 10³ to 10⁶ Ω·cm range, which is why wafer and display handling parts use it.
- Heat out of the partAbout 0.9 W/m·K against 0.25 for unfilled, which also helps a shop hold tighter tolerances.
- Stiffness12 to 14 GPa, the stiffest of the common grades, for fixtures and metrology parts.
- Dry sliding at moderate loadFriction around 0.20 to 0.30, better than unfilled, though a bearing blend beats it.
Look elsewhere when
- Electrical insulationIt conducts. On an insulator this is a functional failure, not a compromise.
- Repeated steamFibre at a machined surface plus lower toughness makes unfilled the better autoclave part.
- ImpactNotched impact of 4 to 6 kJ/m². It is a stiff grade, not a tough one.
- Cost sensitive partsThe most expensive of the four common grades in stock, and hard on tooling.
What changes in the shop
What a shop prices differently for this grade, and what that means for your drawing.
Fit calculator and annealing calculator both use these numbers.
- Tightest tolerance of the family±0.025 mm on small annealed features is realistic, helped by the higher conductivity.
- Conductive dustExtraction matters. Shops running it near electronics handle that deliberately.
- Tool wearAround three times unfilled. Diamond coated tooling is normal on volume.
- AnisotropyExpansion and stiffness differ along and across the extrusion direction, which matters on long fixtures.
Typical parts
Where this grade turns up in practice.
- Wafer handling combs and end effectors
- CMP retaining rings
- Test socket bodies and probe card hardware
- Inspection and alignment fixtures
- Metrology parts
- Dry running bushings at moderate load
Questions about PEEK CF30
More in the full question list.
Is PEEK CF30 conductive?
It is static dissipative rather than a conductor, typically 10³ to 10⁶ Ω·cm. That is enough to bleed charge away from a wafer and far too much to use it as an insulator.
Why does CF30 hold tighter tolerances?
Two reasons. It expands about a third as much as unfilled PEEK, so the part drifts less between the machine and the inspection room, and it conducts heat out of the cut instead of storing it.
Is carbon fibre PEEK the same as carbon filled black PEEK?
No. Black unfilled PEEK is pigmented with carbon black and still insulates. CF30 contains carbon fibre and does not. Buyers confuse the two often enough that it is worth stating the grade in full on the drawing.