ASA (Acrylonitrile Styrene Acrylate)

polymer

amorphous engineering thermoplastic terpolymer

Acrylonitrile styrene acrylateLuran S (BASF)ASA filamentUV-stable ABSoutdoor ABS

ASA (Acrylonitrile Styrene Acrylate) 3D printed component

Density

1.07 g/cm³

UTS (FDM as-built (XY))

38–52 MPa

Elongation (FDM as-built (XY))

5.0–16.0 %

Elastic modulus

2–3 GPa

Glass transition (Tg)

96–105 °C

Mechanical & thermal properties — 2 conditions

Property	FDM as-built (XY)	FDM as-built (Z — upright)
Elastic modulus	2–3 GPa	—
Ultimate tensile strength	38–52 MPa	23–37 MPa
Elongation at break	5.0–16.0 %	2.0–9.0 %
Density	1.05–1.09 g/cm³	—
Glass transition (Tg)	96–105 °C	—
As-built surface Ra	8.0–21.0 µm	—

Values shown as min–max where a spread is reported, otherwise as typical ± unit. Ranges reflect inter-source variation, not single-sample scatter. All values are for AM-processed specimens unless noted.

Unlock the full property data — sign up to additive.tools

Membership · no credit card · no marketing emails. Unlock the full library: 28 articles, 46 materials, 10 processes, 75 papers and more.

Create your account I already have an account

Engineering considerations

UV resistance is the defining engineering case for ASA: for any outdoor application, ASA is the default FDM engineering polymer unless the application requires PC's impact strength, PA66's chemical resistance, or PEEK's temperature performance. The UV performance data from dos-santos-2020 and akato-2020 is compelling — ASA genuinely holds up outdoors without coating.
ASA vs ABS decision: if the application is indoors or UV exposure is short-term (<6 months), ABS is a better choice due to acetone smoothing capability and lower cost. The only other reason to choose ASA over ABS for indoor use is colour stability under fluorescent or strong artificial UV lighting.
Acetone smoothing unavailable — plan surface finishing route: for applications requiring smooth ASA surfaces, the process is: sand to 400 grit wet → filler primer spray → sand 800 grit → UV-stable topcoat. XTC-3D two-part epoxy coating is an alternative that provides both smoothing and UV protection in one step.
Printing parameters close to ABS but not identical: ASA typically requires 5–10°C higher nozzle temperature than ABS at equivalent layer adhesion quality. Start at 250°C nozzle and increase if delamination observed. Bed temperature 90–110°C. Chamber 70–90°C (same as ABS). Cooling fan off or minimal (<20%) to maintain inter-layer adhesion.
Colour retention specification: document the UV exposure test method and duration when specifying ASA for weathering applications. ISO 4892-2 (Xenon arc, 1000h) is the industry standard for outdoor weathering simulation. Request material data to this standard from filament suppliers — commodity ASA grade performance varies significantly.
Bonding ASA parts: acetone bond chemistry (used for ABS) does not work for ASA. Use cyanoacrylate (CA glue) for assembly bonds, two-part epoxy for structural bonds, or MEK (methyl ethyl ketone) as a solvent bond — note MEK requires ventilation. ASA-to-ASA weld bonds with MEK approach ~60% of parent material strength.

Advantages

10× better UV and weathering resistance than ABS: ASA retains >90% tensile strength and colour stability after 1000h Xenon arc (equivalent to >3 years outdoor exposure) vs ABS retaining <50%
Direct drop-in replacement for ABS: ASA uses near-identical print settings — engineers can specify ASA in outdoor applications without requalifying the process
No UV coating required for outdoor applications: ASA inherent UV stability eliminates the cost, process complexity, and field-maintenance burden of UV-protective coatings on ABS
Excellent colour stability: ASA is available in a wide colour range that retains colour under UV; ABS fades and yellows significantly after outdoor exposure
Good heat resistance comparable to ABS: HDT ~88°C at 0.45 MPa — suitable for elevated-temperature outdoor applications (e.g., equipment in direct sun)
Good chemical resistance: resistant to dilute acids, alkalis, oils, and greases — suitable for outdoor industrial environments
Slightly lower warping tendency than ABS: anecdotally observed in practice, attributed to the acrylate rubber phase's lower shrinkage rate on cooling

Limitations

Cannot be acetone vapour smoothed: ASA's acrylate bonds are resistant to acetone — the primary post-processing advantage of ABS (acetone smoothing to Ra 0.2–0.5 µm) is not available for ASA. Surface finishing requires sanding, priming, or epoxy coating
Lower absolute strength than ABS: ASA UTS ~46 MPa vs ABS-M30 ~42–48 MPa — comparable on a like-for-like basis, but premium ABS grades may exceed ASA. For maximum tensile strength, ABS-M30 on Fortus systems is marginally superior
Heated chamber strongly recommended: ASA warps at corners without enclosure heating, particularly for larger parts. Less severe than ABS but non-trivial — enclosure heating 70–90°C recommended for parts >100 mm
Fumes: ASA emits styrene-related VOCs similar to ABS during printing. Not as severe as ABS but still requires enclosure ventilation or air extraction. Not suitable for unventilated spaces
Limited post-processing options vs ABS: acetone smoothing unavailable; bonding with acetone (ABS-specific chemistry) is not effective. Use methylene chloride (DCM) or cyanoacrylate for structural bonds — note DCM is hazardous
Moisture sensitivity: ASA absorbs moisture in storage (less than PA12, more than PETG). Dry at 70°C for 4h if stored unsealed. Wet ASA produces surface roughness and layer delamination similar to ABS
Higher cost than ABS: ASA filament costs 1.5–2.5× more per kilogram than commodity ABS. For indoor applications, ABS is more economical — use ASA only where UV resistance is a requirement

Typical applications

Outdoor signage, housings, and enclosures exposed to UV and weathering without protective coatingsAutomotive exterior trim, mirror housings, and underbonnet components in low-heat zonesAgricultural and horticultural equipment housings — long outdoor exposure in all seasonsMarine and nautical equipment requiring UV and salt-spray resistanceTelecommunications and utility metering equipment for outdoor installationArchitectural models and mock-ups for external display or site weathering trialsRoadside monitoring equipment enclosures, weather station housingsConsumer products for outdoor use: garden tools, sports equipment components, outdoor fixturesUV-exposed jigs and fixtures in outdoor manufacturing or testing environments

ASA (Acrylonitrile Styrene Acrylate)

Mechanical & thermal properties — 2 conditions

Engineering considerations

Advantages

Limitations

Typical applications

Industries

Standards & certifications

Compatible AM processes (1)

Other polymer materials

Related calculators

Related guides