3D Printing Info

Filament comparison

PEEK vs PSU

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

PEEK guidePSU guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PEEK comparisonsMore PSU comparisons
PEEK vs PSU — documented properties and sources
PropertyPEEKHIGHTEMPPSUHIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$531.87/kg median; $296.14–$770.00/kg across 5 dated product listings$168.00/kg median; $168.00–$168.00/kg across 1 dated product listings
Identity & Market
Base polymer / chemistryPolyether ether ketone — a semi-crystalline polyaryletherketone[1]Polysulfone — the lowest-temperature and cheapest of the sulfone family[2]
Densityg/cm³1.30 (ISO 1183)[1][3]1.24 (ISO 1183)[2]
Typical priceUSD/kg1 kg-equivalent spools span 296–770; the middle of the market is about 532[4][5][6]1 kg-equivalent spools cluster near 250[4]
Price range across brandsUSD/kg296-770 across brands and spool sizes; 3D4Makers recycled R-PEEK 296 at 750 g, IEMAI 3D 420 at 1 kg, LEHVOSS Luvocom 3F PEEK 9581 532 at 2 kg, 3DXTech ThermaX PEEK 770 at 500 g[4][5][6]168-250 across formats; 250 g spool $42 (168/kg), 500 g $125 (250/kg) — 3DXTech is the only filament supplier found[4]
Market availability1–5Niche, a handful of specialist brands[4][5][3]Special order, 1–2 makers worldwide[4]
Spool sizes & diameters1.75 and 2.85 mm; 200 g to 2 kg spools[4][5][3]1.75 mm; 250 g and 500 g spools[4]
Typical applicationsAerospace brackets, semiconductor handling, sterilisable medical tooling and downhole parts[1]Transparent high-temperature housings, medical trays and hot-water fittings[2]
Printing Parameters
Nozzle temperature°C380-400 (3DXTech printed-specimen conditions); Victrex quotes a 340-450 melt range for AM 450 FIL[1][3]Not documented
Bed temperature°C130–140 (3DXTech)[1]120–140 (3DXTech)[2]
Enclosure / chamber requirement1–5Actively heated chamber required[7][8]Actively heated chamber required[7][8]
Recommended chamber temperature°CNot less than 150 for semi-crystalline printing (Victrex AM 450 FIL); bed above 150[3]Not documented
Warping tendency1–5Severe — heated chamber needed[7]Not documented
Bed-adhesion difficulty1–5Very difficult — special plates or slurry required[7]Not documented
Overall printing difficulty1–5Expert / industrial hardware only[7][8]Expert / industrial hardware only[7][8]
Extruder requirementAn all-metal hot end rated above 400 °C and a heated chamber; 3DXTech tests at 0.25 mm layer height on a 0.4 mm nozzle[1][7]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[7]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[7]
Abrasiveness1–5Non-abrasive when unfilled[1]Non-abrasive when unfilled[2]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[9]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[10]
Moisture Behaviour
Equilibrium moisture content at ~50 % RH%0.45 at saturation, 23 °C (ISO 62); 0.55 at 100 °C[3]0.30 in 24 h on extruded stock (ASTM D570)[11]
Drying temperature & time120 °C for 5 h, target below 0.020 % moisture (Victrex AM 450 FIL)[3]Not documented
Effect of moisture on strengthNo 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[9]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[10]
Mechanical Properties
Tensile strength (XY)MPa60-100 (printed XY): Victrex AM 450 FIL 60-80 at yield and 3DXTech 100, both ISO 527; 98 at yield injection-moulded[1][3]52 (printed XY, ISO 527, 3DXTech); 81 at break on extruded stock (ASTM D638)[2][11]
Young's modulusMPa3000-4000 (printed XY, ISO 527, Victrex AM 450 FIL); 3720 (3DXTech); 4000 injection-moulded[1][3]2100 (printed XY, ISO 527)[2]
Elongation at break%28 (printed XY, ISO 527) — remarkably ductile for a high-temperature polymer[1]8 (printed XY, ISO 527) against 50 on extruded stock — nearly three times PPSU's printed 3 %[2][12][11]
Flexural strengthMPa130 (printed XY, ISO 178)[1]87 (printed XY, ISO 178)[2]
Flexural modulusMPa2700 (printed XY, ISO 178)[1]2050 (printed XY, ISO 178)[2]
Charpy impact, notchedkJ/m²6.0 (injection-moulded, ISO 179/1eA); unnotched does not break[3]Not documented
Other impact dataIzod notched 7.0 kJ/m2 injection-moulded (ISO 180/A). Printed anisotropy is extreme: VICTREX AM 200 on a Stratasys F900 gives Izod notched 1380-1530 J/m XZ against 30-62 J/m ZX (ASTM D256)[3][13]Izod notched 69 J/m on extruded PSU stock, converted from 1.3 ft-lb/in (ASTM D256)[11]
Layer adhesion / Z tensileMPa20-85 at yield (printed ZX, ISO 527, Victrex AM 450 FIL); the spread is set by chamber temperature and weld quality[3]Not documented
Brittleness1–5Tough — absorbs impact, yields before breaking[1]Moderate[2]
Hardness (scale-specific)Shore A / Shore D / RockwellShore D 84.5 (injection-moulded, ISO 868); Rockwell M100 / R125 on extruded PEEK stock (ASTM D785)[3][14]Rockwell M120 on extruded PSU stock (ASTM D785)[11]
Creep resistance / sustained load1–5Excellent — holds load for years. Victrex rates PEEK for long-term creep; injection-moulded flexural stress at 3.5 % strain falls only from 125 MPa at 23 °C to 85 MPa at 125 °C, and extruded stock is rated to 249 °C continuous[15][3][14]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[11]
Fatigue / repeated-flex resistance1–5Excellent — living hinges viable. Victrex rates PEEK for long-term fatigue as well as creep[15]Not documented
Elasticity / flexibility1–5Rigid[1]Rigid[2]
Z strength as % of XY%71-84 (VICTREX AM 200 LMPAEK printed on the Stratasys F900 and Fortus 450mc, ZX against XZ tensile yield, ASTM D638); unfilled PEEK's own ZX spread is wider[13]Not documented
Thermal Properties
HDT at 0.45 MPa°C140 (printed XY, ISO 75 at 0.45 MPa, 3DXTech)[1]172 (printed XY, ISO 75 at 0.45 MPa, 3DXTech); 181 on extruded stock, converted from 358 °F at 66 psi[2][11]
HDT at 1.8 MPa°C152 (unannealed, ISO 75-2/Af, Victrex AM 450 FIL); 160 on extruded stock (ASTM D648 at 264 psi)[3][14]174 on extruded PSU stock, converted from 345 °F at 264 psi (ASTM D648)[11]
Glass transition (Tg)°C143 (DSC, 3DXTech); Victrex gives onset 143 and midpoint 150 (ISO 11357-2)[1][3]187 (DSC, 3DXTech) and 185 on extruded stock (ASTM D3418), against 230 for PPSU[2][12][11]
Melting point / Vicat°C343 melting (ISO 11357-3, Victrex); VICTREX AM 200 LMPAEK melts at 303[3][13]Not documented
Continuous service temperature°C240 UL 746B relative thermal index, strength (RTI electrical 260, impact 180); Ensinger rates extruded PEEK stock at 249 long term[3][14]141 long-term service on extruded PSU stock, converted from 285 °F[11]
Thermal expansion (CTE)µm/m·K37.8 (extruded PEEK stock, 23-60 °C, ASTM E831; source states 2.1e-5 in/in/°F), rising to 41.9 at 60-100 °C and 55.8 at 100-150 °C[14]55.8 (extruded PSU stock, ASTM D696; source states 3.1e-5 in/in/°F)[11]
Flammability / UL 94UL 94 V-0 at 1.5 mm on the base resin; glow-wire flammability index 960 °C at 2.0 mm (IEC 60695-2-12)[1][3]UL 94 V-0 on extruded PSU stock[11]
Environment & Chemical
Chemical resistanceOutstanding — resistant to almost all solvents and to steam sterilisation[1]Not documented
Water / humidity resistance in service1–5Excellent — essentially unaffected; 0.45 % water at saturation and resistant to steam sterilisation[3][1]Not documented
Electrical & ESD propertiesNot documentedSurface resistance above 10¹³ ohm/sq — an insulator (IEC 60093)[2]
Health & Safety
Fume toxicity1–5Moderate — 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[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[16]
Ventilation / filtration requirement1–5Ventilated room or enclosure recommended[16]Ventilated room or enclosure recommended[16]
Solvents & Solubility
Soluble in95–98 wt% sulphuric acid dissolves it — 10 g per 100 mL at 40–70 °C gives a dark red solution. Laboratory route only.[17][18]Chlorinated hydrocarbons — dichloromethane, chloroform — dissolve polysulfone; ketones and esters attack it as well.[19][18]
Softened or crazed byConcentrated nitric, hydrofluoric, hydrobromic and hydriodic acids attack it; DCM, DMSO and THF swell thin-walled sections.[20][18]Acetone, MEK, ethyl acetate, benzene and toluene craze or stress-crack it; methanol and isopropanol only marginally.[18][19]
Solvent welding & smoothing agentNone — no solvent softens PEEK, so parts are joined thermally or mechanically, never chemically.[20][18]Dichloromethane cement welds PSU and NMP softens residual resin. Both are laboratory reagents.[19]

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. ThermaX PEEK Technical Data Sheet v3 3DXTech · 2026-08 · tds
  2. ThermaX PSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  3. VICTREX AM 450 FIL — datasheet Victrex · 2025-12 · tds
  4. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  5. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  6. IEMAI 3D PEEK 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  7. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  8. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  9. ThermaX PEEK — product page 3DXTech · 2026-08 · vendor
  10. THERMAX PSU — product page (print recommendations) 3DXTech · 2026-08 · doc
  11. TECASON S natural (PSU) — stock shape properties Ensinger · 2026-08 · tds
  12. ThermaX PPSU Technical Data Sheet v3 3DXTech · 2026-08 · tds
  13. VICTREX AM 200 — FDM Material Data Sheet Stratasys · 2024-04 · tds
  14. TECAPEEK natural (PEEK) — stock shape properties Ensinger · 2026-08 · tds
  15. PEEK polymers — product overview Victrex · 2026-08 · doc
  16. 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
  17. The Effects of Sulfonated Poly(ether ether ketone) Ion Exchange Preparation Conditions on Membrane Properties Yee, Zhang & Ladewig, Membranes 3(3) 182–195 · 2013-07 · paper
  18. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds
  19. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  20. What solvents are not compatible with PEEK? — fluidics technical FAQ IDEX Health & Science · 2026-08 · doc