3D Printing Info

Filament comparison

ASA vs PSU

Compare printing settings, strength, heat resistance, dated prices and sources.

ASA guidePSU guide

2 selected · all documented properties

Open these two in the interactive comparisonMore ASA comparisonsMore PSU comparisons
ASA vs PSU — documented properties and sources
PropertyASAASAPSUHIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$28.98/kg median; $17.99–$50.00/kg across 14 dated product listings$168.00/kg median; $168.00–$168.00/kg across 1 dated product listings
Identity & Market
Base polymer / chemistryAcrylonitrile styrene acrylate — ABS with the butadiene rubber phase replaced by an acrylate rubber that has no UV-vulnerable double bonds[1][2]Polysulfone — the lowest-temperature and cheapest of the sulfone family[3]
Densityg/cm³1.05 (Bambu Lab) to 1.13 (PolyLite ASA), ISO 1183; Prusament 1.07[4][5][2]1.24 (ISO 1183)[3]
Typical priceUSD/kg1 kg spools cluster near 30[6][7][8]1 kg-equivalent spools cluster near 250[9]
Price range across brandsUSD/kg18–50 across brands; IEMAI 18, SUNLU 18, Ambrosia 23, Polymaker 26, Bambu Lab 30, YXPOLYER 30, Prusament 41, 3DXTech 50[10][7][6][11][8][9][12][13][14]168-250 across formats; 250 g spool $42 (168/kg), 500 g $125 (250/kg) — 3DXTech is the only filament supplier found[9]
Market availability1–5Stocked by most mainstream brands[6][7][9][8]Special order, 1–2 makers worldwide[9]
Spool sizes & diameters1.75 and 2.85 mm; 0.8, 1, 4 and 10 kg spools[9][8][6]1.75 mm; 250 g and 500 g spools[9]
Typical applicationsOutdoor fittings, signage, automotive exterior trim and anything that has to hold colour and strength in sunlight[15][1]Transparent high-temperature housings, medical trays and hot-water fittings[3]
Diameter tolerance± mm±0.04 (Prusament)[2]Not documented
Printing Parameters
Nozzle temperature°C230–270 across brands; Prusament 260 ± 10, Bambu Lab 240–270, PolyLite 230–260[4][5][2]Not documented
Bed temperature°C75–110; Prusament 110 ± 5, Bambu Lab 80–100, PolyLite 75–95[4][5][2]120–140 (3DXTech)[3]
Enclosure / chamber requirement1–5Enclosure recommended — Polymaker calls a chamber needed at ambient temperature, Bambu Lab requires an enclosed printer and rules out its P1P and A-series machines[5][16]Actively heated chamber required[17][18]
Recommended chamber temperature°C45–60 (Bambu Lab)[4]Not documented
Part cooling fanLow — Prusament 30 % within a 0–50 % range, Bambu Lab 0–80 %, PolyLite off[2][4][5]Not documented
Bed surface & adhesion aidSatin, smooth PEI or powder-coated sheet with a glue stick; Prusa advises a 3 mm or taller brim on large parts[2][16]Not documented
Maximum volumetric flow (mm³/s; see test conditions)mm³/s10–16 (PrusaSlicer guidance for ABS/ASA)[19]Not documented
Warping tendency1–5High — enclosure needed for reliable large parts; Prusa recommends a tall brim and Bambu Lab attributes cracking to cooling stress exceeding interlayer adhesion[2][16]Not documented
Bed-adhesion difficulty1–5Needs a specific surface plus adhesive[2][16]Not documented
Stringing / oozing tendency1–5Slight[5]Not documented
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile[16][2]Expert / industrial hardware only[17][18]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely[16]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[17]
Abrasiveness1–5Non-abrasive[16]Non-abrasive when unfilled[3]
Nozzle clog risk1–5Low — no special hot-end required and clogging is not among the listed drawbacks; Prusa lists no drybox and no hardened nozzle[20][21]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[22]
Heat-creep / jam sensitivity1–5Slightly sensitive[20]Not documented
Hotend requirementNo special hot-end required[20]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — 0.45 % saturated at 25 °C / 55 % RH (Bambu Lab) and 0.40 % equilibrium (Polymaker); Prusa measures only 0.17 % after 7 days at 22 % RH[4][5][2]Not documented
Equilibrium moisture content at ~50 % RH%0.45 saturated at 25 °C / 55 % RH (Bambu Lab); 0.40 equilibrium (Polymaker); 0.17 after 7 days at 24 °C / 22 % RH (Prusa)[4][5][2]0.30 in 24 h on extruded stock (ASTM D570)[23]
Drying temperature & time80 °C for 8 h (Bambu Lab); 70 °C for 7 h (Polymaker)[4][5]Not documented
Symptoms when wetBubbling and popping at the nozzle, stringing, rough surface and weak layers[24]Not documented
Effect of moisture on strengthNo dry-versus-conditioned figures are published for ASA; Polymaker groups the styrenics as moderate-sensitivity and the loss shows as poor layer adhesion rather than a stated strength delta[24]No dry-versus-conditioned figures are published; 3DXTech mandates a 120 °C, 4 h pre-dry before every print because trapped water flashes to steam at these nozzle temperatures[22]
Storage requirementSealed with desiccant; Polymaker rates the styrenics moderate-sensitivity[24]Not documented
Mechanical Properties
Tensile strength (XY)MPa37 ± 3 (Bambu Lab) to 43.8 (PolyLite) printed XY, ISO 527; Prusament 42 ± 1 at yield; Formfutura quotes 47.5 at yield[4][5][2][25]52 (printed XY, ISO 527, 3DXTech); 81 at break on extruded stock (ASTM D638)[3][23]
Young's modulusMPa2379 (PolyLite) to 2450 (Bambu Lab) printed XY, ISO 527; Prusament 1600, Formfutura 2020[4][5][2][25]2100 (printed XY, ISO 527)[3]
Elongation at break%6.7 (PolyLite) to 9.2 (Bambu Lab) at break, printed XY, ISO 527; Formfutura quotes 15 at break, Prusament 3.4 at yield[4][5][25][2]8 (printed XY, ISO 527) against 50 on extruded stock — nearly three times PPSU's printed 3 %[3][26][23]
Flexural strengthMPa64 ± 1 printed horizontal (Prusament, ISO 178); Bambu Lab 65 ± 5, PolyLite 73.4[2][4][5]87 (printed XY, ISO 178)[3]
Flexural modulusMPa1920 ± 130 (Bambu Lab) to 3206 (PolyLite) printed XY, ISO 178; Prusament 2000[4][5][2]2050 (printed XY, ISO 178)[3]
Charpy impact, notchedkJ/m²10.3 (PolyLite) to 19.6 (Bambu Lab) printed XY, ISO 179, notched; Prusament 12 ± 1, Formfutura 18[5][4][2][25]Not documented
Other impact dataCharpy unnotched 25 ± 3 printed horizontal and 38 ± 11 printed vertical (Prusament, ISO 179-1); Bambu Lab 41.0 ± 2.3 printed XY[2][4]Izod notched 69 J/m on extruded PSU stock, converted from 1.3 ft-lb/in (ASTM D256)[23]
Layer adhesion / Z tensileMPa11 ± 1 (Prusa interlayer adhesion test); 31 ± 4 (Bambu Lab) and 32 (PolyLite) printed Z tensile, ISO 527[2][4][5]Not documented
Brittleness1–5Tough — absorbs impact, yields before breaking[4][2]Moderate[3]
Hardness (scale-specific)Shore A / Shore D / Rockwell78 Shore D (Prusa Polymers method)[2]Rockwell M120 on extruded PSU stock (ASTM D785)[23]
Creep resistance / sustained load1–5Moderate — no printed-ASA creep test found; Tg of 98 °C keeps room-temperature service far below softening, unlike PLA[5][2]Good. Ensinger lists high creep resistance as a headline property of extruded PSU stock, which is rated to 173 °C heat deflection at 1.8 MPa[23]
Fatigue / repeated-flex resistance1–5Moderate — fatigue limit at 25 % of tensile strength (8 MPa) on printed specimens, the best of the four polymers in that study[27]Not documented
Elasticity / flexibility1–5Rigid[4]Rigid[3]
Z strength as % of XY%84 (Bambu Lab, printed Z against XY tensile); 73 for PolyLite ASA[4][5]Not documented
Thermal Properties
HDT at 0.45 MPa°C93 (Prusament) to 103 (PolyLite), ISO 75 at 0.45 MPa; Bambu Lab 100[2][5][4]172 (printed XY, ISO 75 at 0.45 MPa, 3DXTech); 181 on extruded stock, converted from 358 °F at 66 psi[3][23]
HDT at 1.8 MPa°C86 (Prusament) to 100 (PolyLite), ISO 75 at 1.8 MPa; Bambu Lab 92[2][5][4]174 on extruded PSU stock, converted from 345 °F at 264 psi (ASTM D648)[23]
Glass transition (Tg)°C98 (PolyLite, DSC)[5]187 (DSC, 3DXTech) and 185 on extruded stock (ASTM D3418), against 230 for PPSU[3][26][23]
Melting point / Vicat°CAmorphous — no melting point; Vicat 105 (PolyLite, ISO 306)[5]Not documented
Continuous service temperature°C93 — Prusa publishes this as the temperature resistance of Prusament ASA[28]141 long-term service on extruded PSU stock, converted from 285 °F[23]
Thermal expansion (CTE)µm/m·K69 ± 17 in XY and 115 ± 24 in the build direction (printed, TMA, 40–70 °C)[29]55.8 (extruded PSU stock, ASTM D696; source states 3.1e-5 in/in/°F)[23]
Flammability / UL 94Flammable; no UL 94 rating published for standard ASA[4]UL 94 V-0 on extruded PSU stock[23]
Environment & Chemical
UV resistance1–5Excellent — designed for permanent outdoor use. After 1000 h of QUV exposure to ASTM G154 Stratasys measured yield strength falling only from 30.5 to 30.3 MPa and stress at break by 3.0 %[15]Not documented
Outdoor durability1000 h QUV per ASTM G154, cycling 8 h at 60 °C and 4 h at 50 °C with condensation: yield 30.5 → 30.3 MPa, stress at break 30.5 → 29.5 MPa, elongation 2.8 → 2.3 %, modulus 1.82 → 1.95 GPa[15]Not documented
Chemical resistanceGood against weak acids, weak alkalis, oils and grease; dissolved by acetone[5]Not documented
Water / humidity resistance in service1–5Good — minor absorption[4]Not documented
Food contactNot food safe[1]Not documented
Biodegradability / compostabilityNot biodegradable[1]Not documented
RecyclabilityNot accepted in household plastic collection[1]Not documented
Electrical & ESD propertiesNot documentedSurface resistance above 10¹³ ohm/sq — an insulator (IEC 60093)[3]
Health & Safety
Fume toxicity1–5High — hazardous VOC such as styrene; enclosure and filtration needed[30][16]Moderate — measurable VOCs and UFPs, ventilation advised. None of these polymers was in the chamber study, and all are processed far above the temperatures it covered[30]
VOC emission rateµg/min12–113 styrene, the range measured across the styrenic filaments tested; ASA itself was not among them[30]Not documented
Ultrafine-particle emission rateparticles/min2 × 10¹⁰ to 9 × 10¹⁰ median for ABS, the closest styrenic tested; ASA itself was not measured[30]Not documented
Hazardous species emittedStyrene. Bambu Lab states ABS and ASA release harmful gases such as styrene at printing temperature, which can be toxic and cause dizziness or nausea. Azimi et al. measured styrene from every styrenic filament tested but did not test ASA itself[16][30]Not documented
Ventilation / filtration requirement1–5Enclosure with carbon and HEPA filtration[30][16]Ventilated room or enclosure recommended[30]
Post-Processing
Sanding & machiningSands well and takes filler before painting[1]Not documented
Gluing & solvent weldingSolvent-welds with acetone[5]Not documented
Vapour / chemical smoothingAcetone vapour smoothing works — ASA dissolves in acetone[5]Not documented
Support material pairingHIPS breaks away or dissolves in d-limonene; Bambu Lab sells a dedicated Support for ABS that also serves ASA[16]Not documented
Dimensional accuracy & detailWarping and cooling-stress cracking are the accuracy limits; Stratasys notes the matte finish as a deliberate aesthetic advantage[16][15]Not documented
Solvents & Solubility
Soluble inAcetone dissolves it (Polymaker); MEK, THF, ethyl acetate and the chlorinated solvents dissolve the styrenic backbone.[31][5]Chlorinated hydrocarbons — dichloromethane, chloroform — dissolve polysulfone; ketones and esters attack it as well.[32][31]
Softened or crazed byLimonene attacks some grades — Prusa reports Prusament ASA Orange flaking apart as layer adhesion fails.[33]Acetone, MEK, ethyl acetate, benzene and toluene craze or stress-crack it; methanol and isopropanol only marginally.[31][32]
Solvent welding & smoothing agentAcetone vapour, ~20 min at 80 °C over 5 mm of liquid (15–40 min across brands); layer adhesion up, tensile slightly down.[34]Dichloromethane cement welds PSU and NMP softens residual resin. Both are laboratory reagents.[32]

Material entries describe families or representative grades, not an interchangeable specification for every spool. Test methods, orientations and conditions may differ. Unknown values are marked “Not documented”. Prices and source dates remain historical snapshots; check the linked guide for product details. Differences highlight text, not a universal winner.

Sources for this comparison

  1. ASA — material basics Polymaker Wiki · 2026-08 · doc
  2. Prusament ASA Technical Datasheet v1.1 Prusa Polymers · 2024-05 · tds
  3. ThermaX PSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  4. Bambu Filament Technical Data Sheet V3.0 — ASA Bambu Lab · 2026-08 · tds
  5. PolyLite ASA Technical Data Sheet Polymaker · 2024-11 · tds
  6. ASA — product page Bambu Lab US Store · 2026-08 · vendor
  7. Polymaker product catalogue Polymaker · 2026-08 · vendor
  8. Printed Solid product catalogue Printed Solid · 2026-08 · vendor
  9. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  10. Filastruder product catalogue Filastruder · 2026-08 · vendor
  11. ZYLtech ASA-GF Glass Fiber filament — product page ZYLtech · 2026-08 · vendor
  12. IEMAI ASA 3D Printing Filament product page IEMAI 3D · 2026-08 · vendor
  13. SUNLU ASA 3D Printer Filament 1 kg SUNLU · 2026-08 · vendor
  14. YXPOLYER ASA Purple product page YXPOLYER · 2026-08 · vendor
  15. ASA — FDM Material Data Sheet (includes 1000 h QUV exposure results) Stratasys · 2026-08 · tds
  16. ABS / ASA / PC Usage Guide Bambu Lab Wiki · 2026-08 · doc
  17. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  18. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  19. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  20. ASA — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  21. Filament Material Guide Prusa Knowledge Base · 2026-08 · doc
  22. THERMAX PSU — product page (print recommendations) 3DXTech · 2026-08 · doc
  23. TECASON S natural (PSU) — stock shape properties Ensinger · 2026-08 · tds
  24. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  25. ApolloX Technical Data Sheet Formfutura · 2026-08 · tds
  26. ThermaX PPSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  27. Mechanical, Fatigue, and Thermal Characterization of ASA, Nylon 12, PC and PC-ABS Manufactured by Fused Filament Fabrication (FFF) Polymers 18(2):302 · 2026-01 · paper
  28. Prusament ASA — material page Prusa Polymers · 2026-08 · doc
  29. Basalt Fiber Composites with Reduced Thermal Expansion for Additive Manufacturing Polymers 14(15):3216 · 2022-08 · paper
  30. Emissions of Ultrafine Particles and Volatile Organic Compounds from Commercially Available Desktop Three-Dimensional Printers with Multiple Filaments (Azimi et al.) Environmental Science & Technology 50(3) 1260-1268 · 2016-01 · paper
  31. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  32. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  33. HIPS — Knowledge Base Prusa Research · 2026-08 · doc
  34. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc