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POM-H GF20

Reinforced grade

ASTM D4181-POM0210 · ISO POM · also POM H, Ramtal

GF20 = 20 % glass-fiber reinforced

Choose for higher stiffness, creep resistance and load-bearing temperature; accept brittleness, anisotropic shrinkage and abrasive wear on tools.

Values for the GF20 condition

Other POM-H grades and fills

POM-H is listed in 10 conditions; see the grade overview at POM-H.

Compare all 10 grades and fillsHide
Grade · open for datasheetBest forYield MPaTensile MPaElong. %Hardness
Impact modified / super-tough
Choose when notch sensitivity or cold impact governs — clips, latches and safety parts — at the cost of half the stiffness and strength.454718075 Shore D
PTFE fiber filled
Use for unlubricated bearings, slides and gears where the lowest coefficient of friction and stick-slip-free motion are required.501580 Shore D
Oil/silicone lubricated
For quiet, low-wear plastic-on-metal gear and slide contacts where oil bleed onto the mating face is acceptable.58602083 Shore D
ESD / static-dissipative
For electronics handling fixtures, fuel-system parts and conveyor components requiring charge dissipation.5858887 Shore D
MoS₂ filled
Economical low-wear bearing/gear grade where PTFE is not required; keeps most of the base stiffness.62621285 Shore D
High viscosity
Pick when maximum toughness, fatigue life and creep resistance matter (gears, snap-fits) and the part is not thin-walled.68724585 Shore D
Heat stabilized / low-emission
Use for continuous 100–120 °C service, hot-water contact or where formaldehyde emission and mold deposit must be minimized.69703086 Shore D
High flow
For thin-wall, multi-cavity and long-flow parts where fill pressure dominates over toughness.70701886 Shore D
GF20This page
20 % glass-fiber reinforced
Choose for higher stiffness, creep resistance and load-bearing temperature; accept brittleness, anisotropic shrinkage and abrasive wear on tools.1053.590 HRM
25 % glass-fiber reinforced
Highest-stiffness standard acetal homopolymer grade for structural brackets and housings under sustained load.1253

What is POM-H GF20?

POM-H GF20 is POM-H in the GF20 grade — choose for higher stiffness, creep resistance and load-bearing temperature; accept brittleness, anisotropic shrinkage and abrasive wear on tools. POM-H GF20 has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 105 MPa (15.2 ksi) — stronger than 79% of polymer grades. Elongation at break is 3.5% and the elastic modulus is 6.5 GPa (0.943 Msi). POM-H GF20 has a density of 1.56 g/cm³ (0.0564 lb/in³), heavier than 91% of polymer grades. Its glass-transition temperature is -60°C (-76 °F).

Advantages

  • Tough — resists crack growth — 4 MPa·√m (3.64 ksi·√in), better than 92% of polymer grades
  • Stiff — 6.5 GPa (0.943 Msi), better than 90% of polymer grades
  • Conducts heat well — 0.31 W/m·K (0.179 BTU/hr·ft·°F), better than 87% of polymer grades
  • High strength — 70 MPa (10.2 ksi), better than 79% of polymer grades
  • Polishes to a fine finish — 70/100, better than 77% of polymer grades

Limitations

  • Heavy — 1.56 g/cm³ (0.0564 lb/in³), worse than 91% of polymer grades
  • Limited ductility — 3.5%, worse than 79% of polymer grades
  • Degrades in UV without stabilisers — 25/100, worse than 76% of polymer grades

POM-H GF20 properties

Typical room-temperature values for POM-H GF20; 13 are specific to this condition. Other listed values are POM-H reference data and may not represent this condition. Bars are the position among polymer grades.

Physical5

POM-H GF20 has a density of 1.56 g/cm³ (0.0564 lb/in³), heavier than 91% of polymer grades. Its glass-transition temperature is -60°C (-76 °F).

Density1.56 g/cm³0.06 lb/in³
Melting Temperature (Tm)175°C347 °F
Glass Transition (Tg)-60°C-76 °F
Water Absorption (24 h)0.25%
Water Absorption (Saturation)0.9%

Mechanical17

POM-H GF20 has a yield strength of 70 MPa (10.2 ksi) and a tensile strength of 105 MPa (15.2 ksi) — stronger than 79% of polymer grades. Elongation at break is 3.5% and the elastic modulus is 6.5 GPa (0.943 Msi).

Elastic (Young's) Modulus6.5 GPa0.94 Msi
Shear Modulus1.1 GPa0.16 Msi
Bulk Modulus4 GPa0.58 Msi
Poisson's Ratio0.37
Tensile Strength (Ultimate)105 MPa15.2 ksi
Yield Strength (0.2% offset)70 MPa10.2 ksi
Elongation at Break3.5%
Compressive Strength110 MPa16 ksi
Compressive Modulus2.9 GPa0.42 Msi
Flexural Strength150 MPa21.8 ksi
Flexural Modulus6 GPa0.87 Msi
Shear Strength65 MPa9.4 ksi
Fracture Toughness (K_IC)4 MPa·√m3.6 ksi·√in
Izod Impact, Notched60 J/m1.1 ft·lbf/in
Hardness, Shore D86 Shore D
Hardness, Rockwell M90 HRM
Hardness, Rockwell R120 HRR

Thermal11

POM-H GF20 is rated for continuous service to 110°C (230 °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 45 µm/m·K (25 µin/in·°F).

Thermal Conductivity0.31 W/m·K0.18 BTU/hr·ft·°F
Specific Heat Capacity1,470 J/kg·K0.35 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)45 µm/m·K25 µin/in·°F
Max Service Temperature (continuous)110°C230 °F
Min Service Temperature-50°C-58 °F
Heat Deflection Temp. @ 0.45 MPa165°C329 °F
Heat Deflection Temp. @ 1.8 MPa158°C316 °F
Vicat Softening Point (B50)160°C320 °F
Flammability (UL 94)HB (1.6 mm); burns readily, no V-rated unfilled homopolymer grades
Limiting Oxygen Index15%
Max Service Temperature (short-term)140°C284 °F

Electrical7

POM-H GF20 is an electrical insulator with a dielectric strength of 20 kV/mm (508 V/mil) and a resistivity of 1×10¹³ Ω·m.

Electrical Resistivity1×10¹³ Ω·m3.94×10²⁰ µΩ·in
Dielectric Strength20 kV/mm508 V/mil
Dielectric Constant (1 MHz)3.7
Dissipation Factor (1 MHz)0.005
Volume Resistivity1×10¹⁵ Ω·cm
Surface Resistivity1×10¹⁵ Ω
Comparative Tracking Index (CTI)600 V

Chemical & Environmental3

Corrosion resistance is very good (72/100), worse than 70% of polymer grades. UV resistance is poor.

Corrosion ResistanceVery good72/100
UV / Weathering ResistancePoor25/100
Chemical Resistance SummaryExcellent against fuels, oils, greases, alcohols, ketones, most solvents and weak alkalis; attacked and depolymerized by strong acids (pH<4), strong oxidizers, hot chlorinated water and phenols; avoid prolonged hot-water/chlorine exposure and UV without stabilizer.

Sustainability4

Producing a kilogram of POM-H GF20 takes about 103 MJ of energy and emits 4.2 kg of CO₂ — less than 54% of polymer grades. Typical recycled content is 0%.

Embodied Energy (primary production)103 MJ/kg44,282 BTU/lb
Embodied Carbon (primary production)4.2 kg CO₂/kg
Embodied Water200 L/kg24 gal/lb
Typical Recycled Content0%

Manufacturability8

POM-H GF20's machinability is good (65/100, better than 66% of polymer grades); weldability fair (40/100); formability fair (45/100).

MachinabilityGood65/100
WeldabilityFair40/100
Formability (cold)Fair45/100
PolishabilityVery good70/100
Mold Shrinkage1%
Melt Flow Rate13 g/10 min
Processing Melt Temperature (typ.)215°C419 °F
Mold Temperature (typ.)90°C194 °F

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with POM-H GF20

Is POM-H easy to machine?

Outstanding to machine — sharp positive-rake tools, high speed, light feed, air or mist cooling; anneal 160 °C (slow cool) before finish cuts on tight-tolerance parts to relieve stress.

Can POM-H be welded?

No solvent cement bonds acetal; join by hot-plate, ultrasonic, spin or laser welding, or use mechanical fasteners; adhesive bonding needs plasma/flame or chromic-acid surface activation.

Can POM-H be formed, bent or molded?

Dry lightly (80 °C, 2–3 h) if wet, hold melt 205–225 °C and never exceed ~230 °C or dwell long (depolymerization/formaldehyde gas); mold at 80–120 °C, use generous gates and thick runners to feed the 2 % shrinkage and avoid voids in thick sections.

What surface finishes work on POM-H?

Machined or molded surfaces polish and burnish well; paints and adhesives require pre-treatment; can be laser-marked, hot-stamped or electroless-plated after specialized etch, but not anodized.

POM-H 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.

ElementSpec limit (wt %)Nominal
heat/antioxidant stabilizer packagehindered phenol + formaldehyde scavenger (nitrogen compound), typical0.3 – 20.8
acid scavenger / lubricantprocessing aid; grade dependent0.1 – 10.3
carbon black / pigmentblack and UV grades only0 – 20.5
glass fiberGF20/GF25 reinforcement variants0 – 250
PTFEDelrin AF bearing variants0 – 200
polyoxymethylene homopolymer (-CH2O-)acetate end-capped formaldehyde homopolymer≥ 97 (balance)

POM-H GF20 — frequently asked

What is POM-H GF20 used for?

POM-H GF20 is typically used for gears, sliding wear pads and bushings. In short: maximum hardness homopolymer.

What is the yield strength of POM-H GF20?

POM-H GF20 has a typical yield strength of 70 MPa (10.2 ksi) and a tensile strength of 105 MPa (15.2 ksi) — stronger than 79% of polymer grades. Strength varies by condition: see the 10 listed tempers.

Is POM-H GF20 easy to machine?

Reasonably — machinability is rated good (65/100, better than 66% of polymer grades). Outstanding to machine — sharp positive-rake tools, high speed, light feed, air or mist cooling; anneal 160 °C (slow cool) before finish cuts on tight-tolerance parts to relieve stress.

Can POM-H GF20 be welded?

With care — weldability is rated fair (40/100). No solvent cement bonds acetal; join by hot-plate, ultrasonic, spin or laser welding, or use mechanical fasteners; adhesive bonding needs plasma/flame or chromic-acid surface activation.

What surface finishes work on POM-H GF20?

Machined or molded surfaces polish and burnish well; paints and adhesives require pre-treatment; can be laser-marked, hot-stamped or electroless-plated after specialized etch, but not anodized.

Can POM-H GF20 be formed, bent or molded?

Dry lightly (80 °C, 2–3 h) if wet, hold melt 205–225 °C and never exceed ~230 °C or dwell long (depolymerization/formaldehyde gas); mold at 80–120 °C, use generous gates and thick runners to feed the 2 % shrinkage and avoid voids in thick sections.

What is the maximum service temperature of POM-H GF20?

POM-H GF20 is rated for continuous use to about 110°C (230 °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-H GF20?

Yes — POM-H GF20 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

  1. Delrin acetal homopolymer product and processing guides — DuPont / Celanese (Delrin brand) (2023)
  2. Tenac / Tenac-C polyacetal technical data — Asahi Kasei (2022)
  3. Ertacetal H / TECAFORM AH stock shape datasheets — Mitsubishi Chemical Advanced Materials / Ensinger (2023)
  4. CAMPUS plastics database — POM homopolymer ISO 10350 datasets — CAMPUS/CWFG (2024)
  5. ISO 9988 Plastics — Polyoxymethylene (POM) moulding and extrusion materials — ISO (2020)
  6. ASTM D6100 Standard Classification for Polyoxymethylene (POM) Molding and Extrusion Materials — ASTM (2020)
  7. Engineered Materials Handbook Vol. 2: Engineering Plastics — 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.