POM HF
Grade
ASTM D4181 · also Delrin
HF = high-flow / thin-wall injection grade
Use for thin-wall, multi-cavity or long-flow-path parts; higher MFR trades some toughness for fill and cycle time.
Values for the HF condition
Other POM grades and fills
POM is listed in 10 conditions; see the grade overview at POM.
Compare all 10 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
Impact modified | Select for snap-fits, clips and cold-climate parts needing high notched impact and ductility, at the cost of stiffness and heat resistance. | 43 | 45 | 120 | 70 Shore D |
PTFE-lubricated bearing grade | Use for unlubricated bearings, slides and gears where the lowest friction and wear rate against steel is required. | 45 | 45 | 15 | 78 Shore D |
Carbon-black conductive / antistatic | Pick for fuel-system parts, conveyor and electronics-handling components that must dissipate static charge. | 47 | 48 | 6 | 82 Shore D |
internally silicone-oil lubricated | Cost-effective friction and noise reduction for gears and clips where mechanicals must stay close to unfilled acetal. | — | 58 | 28 | 79 Shore D |
Molybdenum disulfide filled | Dark, wear-resistant bearing grade for moderate loads where PTFE cost or FDA compliance is not required. | 58 | 60 | 15 | 82 Shore D |
HFThis page High-flow / thin-wall injection grade | Use for thin-wall, multi-cavity or long-flow-path parts; higher MFR trades some toughness for fill and cycle time. | 60 | 61 | 20 | 81 Shore D |
Acetal homopolymer | Pick when maximum stiffness, strength, creep and wear resistance are needed and hot alkali/hot water exposure is limited. | 70 | 70 | 30 | 92 HRM |
10% glass fiber reinforced | Modest stiffness and dimensional-stability boost with much lower shrinkage than unfilled, while retaining some ductility. | — | 85 | 7 | — |
25% glass fiber reinforced | Choose for load-bearing housings, brackets and gears needing high stiffness, low creep and tight dimensional tolerance at elevated temperature. | — | 130 | 3 | 90 HRM |
30% glass fiber reinforced | Maximum-stiffness acetal for structural parts; accept brittleness, abrasive wear on tools and strong shrinkage anisotropy. | — | 135 | 2.5 | — |
What is POM HF?
POM HF is POM in the HF grade — use for thin-wall, multi-cavity or long-flow-path parts; higher MFR trades some toughness for fill and cycle time. POM HF has a yield strength of 60 MPa (8.7 ksi) and a tensile strength of 61 MPa (8.85 ksi) — stronger than 69% of polymer grades. Elongation at break is 20% and the elastic modulus is 2.9 GPa (0.421 Msi). POM HF 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).
Advantages
- Easy to machine — 88/100, better than 92% of polymer grades
- Tough — resists crack growth — 3.8 MPa·√m (3.46 ksi·√in), better than 89% of polymer grades
- Conducts heat well — 0.31 W/m·K (0.179 BTU/hr·ft·°F), better than 87% of polymer grades
- Polishes to a fine finish — 70/100, better than 77% of polymer grades
Limitations
- High mold shrinkage — 2.1%, worse than 86% of polymer grades
- Heavy — 1.41 g/cm³ (0.0509 lb/in³), worse than 81% of polymer grades
- Needs corrosion protection — 70/100, worse than 78% of polymer grades
POM HF properties
Typical room-temperature values for POM HF; 27 are specific to this condition. Other listed values are POM reference data and may not represent this condition. Bars are the position among polymer grades.
Physical5
POM HF 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 HF has a yield strength of 60 MPa (8.7 ksi) and a tensile strength of 61 MPa (8.85 ksi) — stronger than 69% of polymer grades. Elongation at break is 20% and the elastic modulus is 2.9 GPa (0.421 Msi).
Thermal11
POM HF is rated for continuous service to 95°C (203 °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 HF 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 (70/100), worse than 78% of polymer grades. UV resistance is poor.
Sustainability4
Producing a kilogram of POM HF takes about 100 MJ of energy and emits 4.5 kg of CO₂ — less than 61% of polymer grades. Typical recycled content is 0%.
Manufacturability8
POM HF's machinability is excellent (88/100, better than 92% of polymer grades); weldability fair (40/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with POM HF
Is POM easy to machine?
One of the best plastics to machine: sharp positive-rake tools, high speed, light feeds, air or mist cooling; relieve molded-in stress before tight-tolerance finishing and expect springback-free chips.
Can POM be welded?
Hot-plate, ultrasonic, spin and vibration welding all work well; no solvent bonding — adhesive joints require plasma, flame or chromic-acid surface activation.
Can POM be formed, bent or molded?
Dry only if resin is wet (≤0.1%), melt 190–215 °C, mold 80–100 °C, generous gates and full packing; watch ~2% shrinkage, sink and voids in thick sections and never overheat/stagnate melt (formaldehyde release).
What surface finishes work on POM?
Paints and inks need surface pretreatment or special primers; parts polish to a waxy sheen, can be laser-marked, and plating requires a dedicated acetal etch process.
POM 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 |
|---|---|---|
| ethylene oxide comonomercopolymer (POM-C) only; absent in homopolymer POM-H, which is end-capped instead | 1 – 5 | 2.5 |
| heat/acid stabilizer package (antioxidanessential to prevent depolymerization | 0.2 – 1.5 | 0.6 |
| lubricant / mold release | 0 – 1 | 0.3 |
| pigment (carbon black, TiO2 etc.)carbon black also gives UV protection | 0 – 2 | 0.5 |
| oxymethylene (-CH2O-) repeat unitpolyacetal backbone from formaldehyde/trioxane | ≥ 94 (balance) | — |
POM HF — frequently asked
What is POM HF used for?
POM HF is typically used for gears, clips and fuel systems. In short: stiff dimensional acetal.
What is the yield strength of POM HF?
POM HF has a typical yield strength of 60 MPa (8.7 ksi) and a tensile strength of 61 MPa (8.85 ksi) — stronger than 69% of polymer grades. Strength varies by condition: see the 10 listed tempers.
Is POM HF easy to machine?
Yes — machinability is rated excellent (88/100, better than 92% of polymer grades). One of the best plastics to machine: sharp positive-rake tools, high speed, light feeds, air or mist cooling; relieve molded-in stress before tight-tolerance finishing and expect springback-free chips.
Can POM HF be welded?
With care — weldability is rated fair (40/100). Hot-plate, ultrasonic, spin and vibration welding all work well; no solvent bonding — adhesive joints require plasma, flame or chromic-acid surface activation.
What surface finishes work on POM HF?
Paints and inks need surface pretreatment or special primers; parts polish to a waxy sheen, can be laser-marked, and plating requires a dedicated acetal etch process.
Can POM HF be formed, bent or molded?
Dry only if resin is wet (≤0.1%), melt 190–215 °C, mold 80–100 °C, generous gates and full packing; watch ~2% shrinkage, sink and voids in thick sections and never overheat/stagnate melt (formaldehyde release).
What is the maximum service temperature of POM HF?
POM HF is rated for continuous use to about 95°C (203 °F), and briefly to 140°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in POM HF?
Yes — POM HF is available for injection molding with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Hostaform / Celcon POM copolymer product and processing brochures — Celanese (2023)
- Delrin acetal homopolymer design and molding guides — DuPont / Delrin USA (2022)
- CAMPUS plastics ISO datasets for POM-C and POM-H injection grades — CWFG / CAMPUS consortium (2024)
- Engineered Materials Handbook Vol. 2: Engineering Plastics — ASM International (1988)
- ISO 9988 Plastics — Polyoxymethylene (POM) moulding and extrusion materials — ISO (2020)
- ASTM D6100 Standard Classification for Polyoxymethylene (POM) Molding and Extrusion Materials — ASTM (2020)
- Ensinger TECAFORM AH / AD stock shape datasheets — Ensinger (2023)
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.