POM-C
ASTM D4181-POM0110 · ISO POM · also Celcon, Duracon
POM-C is a semi-crystalline acetal copolymer of trioxane with a cyclic ether comonomer (Hostaform, Ultraform), whose C–O–C units give better hot-water, hot-alkali and oxidation resistance than POM-H, plus a wider processing window and fewer centre voids.
POM-C grades and fills
POM-C is supplied in 10 conditions, soft to hard.
Compare all 10 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
elastomer-toughened POM-C | Pick for snap-fits, clips and parts seeing shock or low-temperature impact, at the cost of stiffness and heat resistance. | 45 | 46 | 120 | 60 HRM |
~20% PTFE lubricated bearing grade | Choose for dry-running bearings, slides and wear parts needing the lowest friction and stick-slip-free motion. | 47 | 48 | 15 | 78 Shore D |
X-ray/metal-detectable food-contact grade (blue) | Specify for food, pharma and packaging machinery parts that must be found by inline metal detectors or X-ray if a fragment breaks off. | 50 | 50 | 8 | 82 Shore D |
Flame-retardant grade | Niche halogen-free FR copolymer grades for electrical parts; markedly lower toughness and processing latitude than standard POM-C. | 50 | 52 | 8 | 82 Shore D |
Antistatic / static-dissipative | Use for handling tooling, wafer/electronics fixtures and fuel-contact parts where charge build-up must be bled off (10⁴–10⁹ Ω surface). | 52 | 10 | 80 HRM | |
oil/silicone/PE-wax internally lubricated | For quiet, self-lubricating gear trains and window/seat mechanisms where PTFE cost or colour is an issue. | 53 | 55 | 25 | 79 Shore D |
Molybdenum disulphide lubricated | Low-cost wear grade with slightly higher stiffness and better wear against steel than natural POM-C; MoS2 also nucleates a finer crystalline structure. | 58 | 60 | 18 | 82 Shore D |
UV Stabilized | Use for outdoor or lamp-adjacent parts; carbon black plus HALS/UV absorber greatly slows chalking and surface embrittlement. | 63 | 65 | 30 | 81 Shore D |
25% glass-fiber reinforced | Use where stiffness, creep resistance and elevated-temperature load bearing matter more than toughness or wear on mating parts. | 120 | 3 | 88 HRM | |
30% glass-fiber reinforced | Highest-stiffness standard POM-C grade for structural brackets, pump housings and load-bearing gears at 80–110 °C. | 130 | 2.5 | 90 HRM |
Supply forms, finishes and certifications
Ways POM-C is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
Extruded Stock | Extruded stock shape | Surface finish |
FDA | FDA / EU 10-2011 food-contact and medical-compliant grade | Certification |
StandardDefault | Standard supply | |
UnfilledDefault | Natural/black copolymer, unreinforced | Standard supply |
What is POM-C?
POM-C is a semi-crystalline acetal copolymer of trioxane with a cyclic ether comonomer (Hostaform, Ultraform), whose C–O–C units give better hot-water, hot-alkali and oxidation resistance than POM-H, plus a wider processing window and fewer centre voids. It combines rigidity, dimensional stability, low moisture uptake and excellent machinability (65 MPa tensile, 32 % elongation, 100 °C service) in rod, plate and moulded gears, bearings and valve parts. Limits are poor resistance to strong acids and oxidisers, UL94 HB only, weak unstabilised UV ageing and formaldehyde release above ~230 °C; POM-H gives higher stiffness and wear. POM-C has a density of 1.41 g/cm³ (0.0509 lb/in³), heavier than 81% of polymer grades. Its glass-transition temperature is -60°C (-76 °F). POM-C has a yield strength of 63 MPa (9.14 ksi) and a tensile strength of 65 MPa (9.43 ksi) — stronger than 74% of polymer grades. Elongation at break is 32% and the elastic modulus is 2.8 GPa (0.406 Msi).
What is POM-C used for?
- Chemical-resistant gears
- Bearings and bushings
- Slide plates and wear guides
- Valve bodies and seats
- Pump housings and impellers
- Conveyor chain components
- Precision mechanical housings
- Snap-fit clips and fasteners
Advantages
- Tough — resists crack growth — 4 MPa·√m (3.64 ksi·√in), better than 92% of polymer grades
- Easy to machine — 88/100, better than 92% of polymer grades
- Conducts heat well — 0.31 W/m·K (0.179 BTU/hr·ft·°F), better than 87% of polymer grades
Limitations
- Heavy — 1.41 g/cm³ (0.0509 lb/in³), worse than 81% of polymer grades
- High mold shrinkage — 2%, worse than 81% of polymer grades
POM-C properties
Typical room-temperature values in the Unfilled condition; bars are the position among polymer grades.
Physical6
POM-C has a density of 1.41 g/cm³ (0.0509 lb/in³), heavier than 81% of polymer grades. Its glass-transition temperature is -60°C (-76 °F).
Mechanical17
POM-C has a yield strength of 63 MPa (9.14 ksi) and a tensile strength of 65 MPa (9.43 ksi) — stronger than 74% of polymer grades. Elongation at break is 32% and the elastic modulus is 2.8 GPa (0.406 Msi).
Thermal11
POM-C is rated for continuous service to 100°C (212 °F). It conducts heat at 0.31 W/m·K (0.179 BTU/hr·ft·°F), better than 87% of polymer grades. Thermal expansion is 110 µm/m·K (61.1 µin/in·°F).
Electrical7
POM-C is an electrical insulator with a dielectric strength of 20 kV/mm (508 V/mil) and a resistivity of 1×10¹² Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (72/100), worse than 70% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of POM-C takes about 100 MJ of energy and emits 3.9 kg of CO₂ — less than 61% of polymer grades. Typical recycled content is 0%.
Manufacturability8
POM-C's machinability is excellent (88/100, better than 92% of polymer grades); weldability fair (35/100); formability fair (35/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the polymer family
Yield strength against density for every polymer grade FabDigit runs. POM-C is highlighted; hover a dot for its name, or open the interactive family chart.
Working with POM-C
Is POM-C easy to machine?
Excellent — sharp positive-rake tools, high speed and light feed give chip-free, mirror-like surfaces; anneal (140–150 °C, slow cool) before finish cuts on thick or tight-tolerance parts.
Can POM-C be welded?
Poor to fair — hot-plate, ultrasonic, vibration and spin welding work with a joint design; solvent bonding is impossible and adhesives need flame/plasma or chromic-acid surface activation.
Can POM-C be formed, bent or molded?
Injection mould at 190–210 °C melt (never above ~230 °C or 20 min residence — decomposes to formaldehyde), mould 80–100 °C, generous gates and 2 % shrink allowance; extrusion of rod/plate needs slow, controlled cooling to avoid centre voids.
Manufacturability
The process limits FabDigit's quote engine applies to POM-C. Design inside these and the part quotes instantly; outside them it routes to an engineer.
CNC machining
| Machinability | Excellent88 / 100 |
|---|---|
| ISO material group | N.8 |
| Cutting speed (rough / finish) | 420 / 520 m/min |
| Minimum wall | 0.5 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 10× diameter |
| Best surface (machined / polished) | Ra 0.8 / 0.4 µm |
| Hardenable after machining | No |
Sheet metal
| Formability | Fair35 / 100 |
|---|---|
| Weldability | Better35 / 100 |
Injection molding
| Mold shrinkage | — |
|---|---|
| Wall thickness | — – — |
| Recommended draft | — |
| Pre-drying | — |
POM-C 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 |
|---|---|---|
| comonomer (ethylene oxide / 1,3-dioxolanC–C linkages that block unzipping and give alkali/hot-water resistance | 1 – 4 | 2 |
| stabilizers (antioxidant, formaldehyde shindered phenol + amine/nitrogen scavenger package | 0.2 – 1 | 0.5 |
| pigment / carbon blackblack and UV grades only | 0 – 2 | 0.3 |
| oxymethylene (–CH2O–) unitsfrom trioxane polymerization | ≥ 96 (balance) |
What surface finishes work on POM-C?
Machined or moulded surfaces are naturally low-friction and can be buffed; paint, print and plating require pre-treatment (etch/primer) because POM is chemically inert and non-polar.
Surface treatments FabDigit runs on polymer parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Injection Molding Coating
Organic Coating
Metallization / Functional
Equivalent designations
Standards and trade names that resolve to POM-C in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- D4181-POM0110
- ISO
- POM
- Trade names
- CelconDuraconHostaformIupitalKepitalPOM CTenac CUltraformTecaform
- Also called
- AcetalPolyoxymethylene CopolymerAcetal CopolymerErtacetal C
How much does POM-C cost?
POM-C is a standard-cost polymer ($$), cheaper than about 81% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
POM-C — frequently asked
What is POM-C used for?
POM-C is typically used for chemical-resistant gears, bearings and bushings, slide plates and wear guides, valve bodies and seats, pump housings and impellers and conveyor chain components. In short: strong precise copolymer.
What is the yield strength of POM-C?
POM-C has a typical yield strength of 63 MPa (9.14 ksi) and a tensile strength of 65 MPa (9.43 ksi) — stronger than 74% of polymer grades. Strength varies by condition: see the 10 listed tempers.
Is POM-C easy to machine?
Yes — machinability is rated excellent (88/100, better than 92% of polymer grades). Excellent — sharp positive-rake tools, high speed and light feed give chip-free, mirror-like surfaces; anneal (140–150 °C, slow cool) before finish cuts on thick or tight-tolerance parts.
Can POM-C be welded?
With care — weldability is rated fair (35/100). Poor to fair — hot-plate, ultrasonic, vibration and spin welding work with a joint design; solvent bonding is impossible and adhesives need flame/plasma or chromic-acid surface activation.
What surface finishes work on POM-C?
Machined or moulded surfaces are naturally low-friction and can be buffed; paint, print and plating require pre-treatment (etch/primer) because POM is chemically inert and non-polar.
Can POM-C be formed, bent or molded?
Injection mould at 190–210 °C melt (never above ~230 °C or 20 min residence — decomposes to formaldehyde), mould 80–100 °C, generous gates and 2 % shrink allowance; extrusion of rod/plate needs slow, controlled cooling to avoid centre voids.
What is the maximum service temperature of POM-C?
POM-C is rated for continuous use to about 100°C (212 °F), and briefly to 140°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
How much does POM-C cost?
POM-C is a standard-cost polymer ($$), cheaper than about 81% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in POM-C?
Yes — POM-C is available for CNC machining, sheet metal and injection molding with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- ISO 9988-1/-2 Plastics — Polyoxymethylene (POM) moulding and extrusion materials — ISO (2020)
- ASTM D6100 Standard Classification for Polyoxymethylene (POM) Molding and Extrusion Materials — ASTM (2020)
- Hostaform C 9021 / GV1-30 / TF product data sheets — Celanese (2023)
- Ultraform (POM) product range brochure — BASF (2022)
- TECAFORM AH natural / LA / ELS / MDblue datasheets — Ensinger (2023)
- Ertacetal C stock shapes data — Mitsubishi Chemical Advanced Materials (2022)
- CAMPUS plastics database — POM-C single-point data (ISO 10350) — CWFG (2024)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.