ASA GF20
Reinforced grade
ASTM D4785 · GB GB/T 24151 · ISO 2580-2 ASA · also Centrex, Geloy
GF20 = 20% glass fiber reinforced
Choose 20% glass fiber reinforcement when stiffness of 5.5 GPa, creep resistance and lower CTE govern; elongation falls to 3% and impact toughness and surface appearance drop.
Values for the GF20 condition
Other ASA grades and fills
ASA is listed in 7 conditions; see the grade overview at ASA.
Compare all 7 grades and fillsHide
| Grade · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness |
|---|---|---|---|---|---|
FDM part, XY orientation, as built | Use for FDM parts as built in the XY orientation, 34 MPa tensile and 1.9 GPa modulus, and design around the anisotropy because Z interlayer strength is markedly lower. | 32 | 34 | 8 | 76 Shore D |
High impact / impact modified | Choose the impact-modified grade with higher acrylate rubber content for outdoor structural parts needing 40% elongation or toughness at low temperature; modulus stays 1.9 GPa. | 38 | 40 | 40 | 74 Shore D |
FDM filament grade | Use the 1.75/2.85 mm filament grade optimized for FDM extrusion when outdoor prints need weatherability and less warp than ABS; print in an enclosed, heated chamber. | 42 | 44 | 20 | 77 Shore D |
Flame retardant | Pick the flame-retardant modification when UL 94 V-0 is required, as in outdoor electrical enclosures and PV junction boxes; impact toughness and melt flow drop slightly. | 43 | 44 | 12 | 79 Shore D |
pigmented weather-resistant compound | Pick the pigmented weather-resistant compound (usually carbon black or inorganic colors) when outdoor color and gloss retention govern; tensile stays 46 MPa, elongation 22%. | 44 | 46 | 22 | 78 Shore D |
Heat resistant / high heat grade | Pick the heat-resistant grade, copolymerized or alloyed for a higher glass transition, for dark automotive exterior parts that heat up under solar load; service to 90 °C. | 49 | 50 | 15 | 80 Shore D |
GF20This page 20% glass fiber reinforced | Choose 20% glass fiber reinforcement when stiffness of 5.5 GPa, creep resistance and lower CTE govern; elongation falls to 3% and impact toughness and surface appearance drop. | — | 85 | 3 | 85 HRM |
What is ASA GF20?
ASA GF20 is ASA in the GF20 grade — choose 20% glass fiber reinforcement when stiffness of 5.5 GPa, creep resistance and lower CTE govern; elongation falls to 3% and impact toughness and surface appearance drop. ASA GF20 has a yield strength of 45 MPa (6.53 ksi) and a tensile strength of 85 MPa (12.3 ksi) — weaker than 58% of polymer grades. Elongation at break is 3% and the elastic modulus is 5.5 GPa (0.798 Msi). ASA GF20 has a density of 1.22 g/cm³ (0.0441 lb/in³), heavier than 61% of polymer grades. Its glass-transition temperature is 105°C (221 °F).
Advantages
- Low, predictable mold shrinkage — 0.25%, better than 93% of polymer grades
- Stiff — 5.5 GPa (0.798 Msi), better than 88% of polymer grades
- Good UV / weathering resistance — 80/100, better than 86% of polymer grades
- Polishes to a fine finish — 70/100, better than 77% of polymer grades
Limitations
- Limited ductility — 3%, worse than 83% of polymer grades
- Needs corrosion protection — 70/100, worse than 78% of polymer grades
- Poor heat conductor — 0.17 W/m·K (0.0982 BTU/hr·ft·°F), worse than 75% of polymer grades
ASA GF20 properties
Typical room-temperature values for ASA GF20; 15 are specific to this condition. Other listed values are ASA reference data and may not represent this condition. Bars are the position among polymer grades.
Physical5
ASA GF20 has a density of 1.22 g/cm³ (0.0441 lb/in³), heavier than 61% of polymer grades. Its glass-transition temperature is 105°C (221 °F).
Mechanical15
ASA GF20 has a yield strength of 45 MPa (6.53 ksi) and a tensile strength of 85 MPa (12.3 ksi) — weaker than 58% of polymer grades. Elongation at break is 3% and the elastic modulus is 5.5 GPa (0.798 Msi).
Thermal11
ASA GF20 is rated for continuous service to 90°C (194 °F). It conducts heat at 0.17 W/m·K (0.0982 BTU/hr·ft·°F), worse than 75% of polymer grades. Thermal expansion is 35 µm/m·K (19.4 µin/in·°F).
Electrical7
ASA GF20 is an electrical insulator with a dielectric strength of 25 kV/mm (635 V/mil) and a resistivity of 1×10¹⁴ Ω·m.
Chemical & Environmental3
Corrosion resistance is very good (70/100), worse than 78% of polymer grades. UV resistance is very good.
Sustainability4
Producing a kilogram of ASA GF20 takes about 96 MJ of energy and emits 3.9 kg of CO₂ — less than 67% of polymer grades. Typical recycled content is 5%.
Manufacturability8
ASA GF20's machinability is good (60/100, better than 51% of polymer grades); weldability very good (70/100); formability very good (75/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ASA GF20
Is ASA easy to machine?
Amorphous and easy to cut with sharp positive-rake tools at high spindle speed and low feed; keep chips clear and cool the cut so frictional heat does not melt and re-weld the surface. Glass-filled grades require carbide tooling.
Can ASA be welded?
Ultrasonic, hot-plate and vibration/friction welding all work, and solvent bonding with MEK or dichloromethane is possible; cyanoacrylate and epoxy adhesives also bond well.
Can ASA be formed, bent or molded?
Dry 2–4 h at 80 °C before moulding, run 230–260 °C melt with 50–80 °C tool, and allow about 0.4–0.7 % shrinkage. Sheet vacuum-thermoforms.
What surface finishes work on ASA?
Weatherability is in the polymer, so outdoor parts often need no paint; high-gloss and grained tool textures reproduce well. Electroplating uses ABS-type pretreatment with slightly lower adhesion than ABS, and acrylic or PU paints can be sprayed.
ASA 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 |
|---|---|---|
| styrenestyrene monomer unit | 55 – 75 | 65 |
| acrylonitrileacrylonitrile monomer unit | 15 – 25 | 21 |
| acrylate rubber (n-butyl acrylate)saturated acrylate rubber graft phase, gives weatherability | 8 – 30 | 14 |
| stabilizers/pigmentsantioxidant/HALS/UV absorber/pigments | 0.2 – 3 | 1 |
ASA GF20 — frequently asked
What is ASA GF20 used for?
ASA GF20 is typically used for outdoor equipment housings, automotive mirror housings and exterior trim, building and window profiles, roof drainage and gutter components, antenna radomes and garden tool bodies. In short: weather resistant tough.
What is the yield strength of ASA GF20?
ASA GF20 has a typical yield strength of 45 MPa (6.53 ksi) and a tensile strength of 85 MPa (12.3 ksi) — weaker than 58% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is ASA GF20 easy to machine?
Reasonably — machinability is rated good (60/100, better than 51% of polymer grades). Amorphous and easy to cut with sharp positive-rake tools at high spindle speed and low feed; keep chips clear and cool the cut so frictional heat does not melt and re-weld the surface. Glass-filled grades require carbide tooling.
Can ASA GF20 be welded?
Yes — weldability is rated very good (70/100). Ultrasonic, hot-plate and vibration/friction welding all work, and solvent bonding with MEK or dichloromethane is possible; cyanoacrylate and epoxy adhesives also bond well.
What surface finishes work on ASA GF20?
Weatherability is in the polymer, so outdoor parts often need no paint; high-gloss and grained tool textures reproduce well. Electroplating uses ABS-type pretreatment with slightly lower adhesion than ABS, and acrylic or PU paints can be sprayed.
Can ASA GF20 be formed, bent or molded?
Dry 2–4 h at 80 °C before moulding, run 230–260 °C melt with 50–80 °C tool, and allow about 0.4–0.7 % shrinkage. Sheet vacuum-thermoforms.
What is the maximum service temperature of ASA GF20?
ASA GF20 is rated for continuous use to about 90°C (194 °F), and briefly to 95°C. Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Can FabDigit make parts in ASA GF20?
Yes — ASA GF20 is available for CNC machining, sheet metal, injection molding and 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.
Sources
- Luran S ASA — INEOS Styrolution (2022)
- Geloy ASA Resin Product Data — SABIC (2021)
- Centrex ASA/AES Weatherable Polymers — INEOS Styrolution (2020)
- CAMPUS Plastics ISO 10350 (ASA) — CAMPUS/CWFG (2023)
- Engineered Materials Handbook Vol.2: Engineering Plastics — ASM International (1988)
- ISO 19064-1 Plastics — ASA moulding and extrusion materials — ISO (2015)
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.