FFKM · certified grade · default condition
FFKM Semiconductor Grade
Properties of the Semiconductor Grade condition, compared with the other FFKM grades.
Default choice for wafer-fab chamber, gate valve, slit-valve and wet-bench seals where particle generation, plasma erosion and metal-ion contamination matter.
What is FFKM Semiconductor Grade?
FFKM Semiconductor Grade is FFKM in a Semiconductor Grade certified grade — default choice for wafer-fab chamber, gate valve, slit-valve and wet-bench seals where particle generation, plasma erosion and metal-ion contamination matter. FFKM Semiconductor Grade has a tensile strength of 17 MPa (2.47 ksi), weaker than 70% of polymer grades. Elongation at break is 140% and the elastic modulus is 0.01 GPa (0.0016 Msi). FFKM Semiconductor Grade has a density of 2 g/cm³ (0.0723 lb/in³), heavier than 98% of polymer grades. Its glass-transition temperature is -3°C (27 °F).
Advantages
- High service temperature — 300°C (572 °F), better than 99% of polymer grades
- Good corrosion resistance — 98/100, better than 99% of polymer grades
- Good UV / weathering resistance — 95/100, better than 95% of polymer grades
Limitations
- High embodied carbon — 28 kg CO₂/kg, worse than 100% of polymer grades
- Heavy — 2 g/cm³ (0.0723 lb/in³), worse than 98% of polymer grades
- High mold shrinkage — 3.5%, worse than 98% of polymer grades
- Difficult to machine — 20/100, worse than 97% of polymer grades
- Low stiffness — 0.01 GPa (0.0016 Msi), worse than 81% of polymer grades
FFKM Semiconductor Grade properties
Typical room-temperature values for FFKM Semiconductor Grade — 6 properties are specific to this condition; the rest are grade-level values shared by every FFKM grade. Each bar shows where the value sits among the polymer grades in FabDigit's library — further right is higher.
Physical3
FFKM Semiconductor Grade has a density of 2 g/cm³ (0.0723 lb/in³), heavier than 98% of polymer grades. Its glass-transition temperature is -3°C (27 °F).
Mechanical7
FFKM Semiconductor Grade has a tensile strength of 17 MPa (2.47 ksi), weaker than 70% of polymer grades. Elongation at break is 140% and the elastic modulus is 0.01 GPa (0.0016 Msi).
Thermal7
FFKM Semiconductor Grade is rated for continuous service to 300°C (572 °F). It conducts heat at 0.22 W/m·K (0.127 BTU/hr·ft·°F), better than 60% of polymer grades. Thermal expansion is 230 µm/m·K (127.8 µin/in·°F).
Electrical4
FFKM Semiconductor Grade is an electrical insulator with a dielectric strength of 18 kV/mm (457.2 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental3
Corrosion resistance is excellent (98/100), better than 99% of polymer grades. UV resistance is excellent.
Sustainability3
Producing a kilogram of FFKM Semiconductor Grade takes about 400 MJ of energy and emits 28 kg of CO₂ — more than 100% of polymer grades. Typical recycled content is 0%.
Manufacturability3
FFKM Semiconductor Grade's machinability is poor (20/100, worse than 97% of polymer grades).
Common Calculations4
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other FFKM grades and fills
FFKM is also supplied in 7 other conditions. The full side-by-side table is on the FFKM overview.
- Semiconductor GradeDefaultDefault choice for wafer-fab chamber, gate valve, slit-valve and wet-bench seals where particle generation, plasma erosion and metal-ion contamination matter.17 MPa tensile
Working with FFKM Semiconductor Grade
Is FFKM easy to machine?
Not a machining material — parts are net-shape moulded; trimming is done cryogenically or by waterjet, and any secondary cutting must avoid heat and tearing.
Can FFKM be welded?
Cannot be welded; joints are made by co-moulding or bonded splices, and spliced rings lose a large part of the burst/extrusion strength.
Can FFKM be formed, bent or molded?
Compression or injection moulded at roughly 170–205 °C with a long oven post-cure (up to ~305 °C, hours to days) to develop full compression-set and heat resistance; mould shrinkage is high (~3–4 %) so tooling must be scaled per compound.
What surface finishes work on FFKM?
Supplied as-moulded with minimal flash; semiconductor grades are washed/extracted and cleanroom packaged, and no coating or painting is practical on the low-energy fluorinated surface.
FFKM chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| tetrafluoroethylene (TFE)backbone comonomer, wt% of polymer | 50 – 70 | 62 |
| perfluoromethylvinyl ether (PMVE)flexibilising comonomer | 28 – 45 | 36 |
| cure-site monomer (e.g. perfluoro nitriltriazine or peroxide cross-link site | 0.3 – 3 | 1.5 |
| filler (carbon black, silica, TiO2, BaSOphr in the compound; grade dependent | 5 – 30 | 15 |
| curative / co-agent package | 0.5 – 4 | 2 |
FFKM Semiconductor Grade — frequently asked
What is FFKM Semiconductor Grade used for?
FFKM Semiconductor Grade is typically used for semiconductor plasma chamber seals, wafer wet-process O-rings, chemical reactor and valve seals, hot oilfield downhole seals, steam and amine service gaskets and aerospace fuel and hydraulic seals. In short: semiconductor-grade perfluoroelastomer.
What is the tensile strength of FFKM Semiconductor Grade?
FFKM Semiconductor Grade has a typical tensile strength of 17 MPa (2.47 ksi) — weaker than 70% of polymer grades. Strength varies by condition: see the 8 listed tempers.
Is FFKM Semiconductor Grade easy to machine?
Not especially — machinability is rated poor (20/100, worse than 97% of polymer grades). Not a machining material — parts are net-shape moulded; trimming is done cryogenically or by waterjet, and any secondary cutting must avoid heat and tearing.
Can FFKM Semiconductor Grade be welded?
Cannot be welded; joints are made by co-moulding or bonded splices, and spliced rings lose a large part of the burst/extrusion strength.
What surface finishes work on FFKM Semiconductor Grade?
Supplied as-moulded with minimal flash; semiconductor grades are washed/extracted and cleanroom packaged, and no coating or painting is practical on the low-energy fluorinated surface.
Can FFKM Semiconductor Grade be formed, bent or molded?
Compression or injection moulded at roughly 170–205 °C with a long oven post-cure (up to ~305 °C, hours to days) to develop full compression-set and heat resistance; mould shrinkage is high (~3–4 %) so tooling must be scaled per compound.
What is the maximum service temperature of FFKM Semiconductor Grade?
FFKM Semiconductor Grade is rated for continuous use to about 300°C (572 °F), and briefly to 340°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in FFKM Semiconductor Grade?
Yes — FFKM Semiconductor Grade is available for sheet metal and injection molding with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Kalrez Perfluoroelastomer Parts — product and compound selection data — DuPont (2023)
- Chemraz perfluoroelastomer compound datasheets — Greene Tweed (2022)
- ASTM D1418 / ASTM D2000 — rubber classification (FFKM) — ASTM (2022)
- ASTM D412 / D395 / D2240 — tensile, compression set, durometer hardness of elastomers — ASTM (2021)
- ASM Engineered Materials Handbook Vol. 2 — Engineering Plastics/Elastomers — ASM International (1988)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.