ASA HI
Grade
ASTM D4785 · GB GB/T 24151 · ISO 2580-2 ASA · also Centrex, Geloy
HI = 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.
Values for the HI 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 |
HIThis page 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 |
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 HI?
ASA HI is ASA in the HI grade — 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. ASA HI has a yield strength of 38 MPa (5.51 ksi) and a tensile strength of 40 MPa (5.8 ksi) — weaker than 64% of polymer grades. Elongation at break is 40% and the elastic modulus is 1.9 GPa (0.276 Msi). ASA HI has a density of 1.07 g/cm³ (0.0387 lb/in³), lighter than 68% of polymer grades. Its glass-transition temperature is 105°C (221 °F).
Advantages
- Good UV / weathering resistance — 88/100, better than 90% of polymer grades
- Polishes to a fine finish — 70/100, better than 77% of polymer grades
Limitations
- 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 HI properties
Typical room-temperature values for ASA HI; 27 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 HI has a density of 1.07 g/cm³ (0.0387 lb/in³), lighter than 68% of polymer grades. Its glass-transition temperature is 105°C (221 °F).
Mechanical15
ASA HI has a yield strength of 38 MPa (5.51 ksi) and a tensile strength of 40 MPa (5.8 ksi) — weaker than 64% of polymer grades. Elongation at break is 40% and the elastic modulus is 1.9 GPa (0.276 Msi).
Thermal11
ASA HI is rated for continuous service to 78°C (172 °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 85 µm/m·K (47.2 µin/in·°F).
Electrical7
ASA HI 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 excellent.
Sustainability4
Producing a kilogram of ASA HI 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 HI's machinability is good (57/100, worse than 56% of polymer grades); weldability good (62/100); formability good (55/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ASA HI
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 HI — frequently asked
What is ASA HI used for?
ASA HI 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 HI?
ASA HI has a typical yield strength of 38 MPa (5.51 ksi) and a tensile strength of 40 MPa (5.8 ksi) — weaker than 64% of polymer grades. Strength varies by condition: see the 7 listed tempers.
Is ASA HI easy to machine?
Reasonably — machinability is rated good (57/100, worse than 56% 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 HI be welded?
Yes — weldability is rated good (62/100). 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 HI?
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 HI 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 HI?
ASA HI is rated for continuous use to about 78°C (172 °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 HI?
Yes — ASA HI 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.