3D Printing Info

Filament comparison

Magnetic vs PEI 9085

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

Magnetic filament guidePEI (ULTEM 9085) guide

2 selected · all documented properties

Open these two in the interactive comparisonMore Magnetic comparisonsMore PEI 9085 comparisons
Magnetic vs PEI 9085 — documented properties and sources
PropertyMagnetic filamentSPECIALTYPEI (ULTEM 9085)HIGHTEMP
Market snapshot
Listing priceUSD/kg; dated snapshots$64.99/kg median; $64.99–$64.99/kg across 1 dated product listings$309.80/kg median; $220.00–$392.00/kg across 6 dated product listings
Identity & Market
Base polymer / chemistryPLA loaded with ferromagnetic iron powder, so printed parts respond to magnets[1]Polyetherimide, ULTEM 9085 grade — the flame-retardant PEI used for aircraft interiors[2]
Densityg/cm³About 1.85 (Proto-pasta manufacturer figure) — 1.5× standard PLA[1]1.34 (ISO 1183, 3DXTech) against 1.27 specific gravity on moulded plaques (ASTM D792, Stratasys) — the two suppliers disagree[2][3]
Typical priceUSD/kg1 kg spools cluster near 65[4]1 kg-equivalent spools cluster near 298[5][6][7][8]
Price range across brandsUSD/kg64–70 across formats; 1 kg spool 65, 500 g 70, 2 kg 70[4]220-392 across brands and formats; 3DXTech ThermaX PEI 9085 220 at 2 kg, 3D4Makers 270 at 2 kg, Fiberlogy 298 at 500 g, Kimya 321 at 500 g, IEMAI 3D 385 at 1 kg, 3DXTech CarbonX PEI 9085+CF 392[5][6][7][8][9]
Market availability1–5Niche, a handful of specialist brands[4]Niche, a handful of specialist brands[5][6][7][8]
Spool sizes & diameters1.75 and 2.85 mm; 0.1, 0.5, 1 and 2 kg spools[4]1.75 and 2.85 mm; 250 g to 2 kg spools, plus Stratasys canisters[5][8][3]
Typical applicationsSensor targets, magnetic fixtures, and props that need to stick to a magnet or rust deliberately[1]Aircraft interior parts and rail rolling stock, where the flame, smoke and toxicity rating is the requirement[2]
Printing Parameters
Nozzle temperature°C192 (Proto-pasta)[1]Not documented
Bed temperature°C60 (Proto-pasta)[1]130–140 (3DXTech)[2]
Enclosure / chamber requirement1–5Open frame is fine[1]Actively heated chamber required[10][11]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s1.6–2.4 at Proto-pasta's 20–30 mm/s on a 0.4 mm nozzle at 0.2 mm layer[1]Not documented
Warping tendency1–5Not documentedSevere — heated chamber needed[10]
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile; slow, and brittle in filament form[1]Expert / industrial hardware only[10][11]
Extruder requirementProto-pasta advises an extrusion width 0.05 mm larger than the nozzle and warns feeding is inconsistent below 0.4 mm and on Bowden machines[1]Not documented
Hardware Wear & Reliability
Nozzle hardness required1–4Brass acceptable; hardened steel for volume work[1]Brass fine indefinitely for unfilled grades, but brass softens near these nozzle temperatures — hardened or plated hot ends are the norm[10]
Abrasiveness1–5Moderately abrasive — metal fill[1]Non-abrasive when unfilled[2]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle; Prusa lists metal-filled composites as a higher clogging risk and recommends a 0.6 mm nozzle minimum[12]Moderate — needs dry filament and a clean nozzle; 3DXTech lists no special nozzle concerns but a mandatory 120 °C pre-dry before every print[13]
Hotend requirementProto-pasta recommends a wear-resistant or larger nozzle for longer service intervals[1]Not documented
Moisture Behaviour
Effect of moisture on strengthPolymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[14]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[13]
Mechanical Properties
Tensile strength (XY)MPaNot documented63-77 at break (printed XZ, ASTM D638, Stratasys F900/F3300/Fortus 450mc, three tips and two colours); 54 (printed XY, ISO 527, 3DXTech)[3][2]
Young's modulusMPaNot documented2040-2540 (printed XZ, ASTM D638, Stratasys); 2050 (printed XY, ISO 527, 3DXTech)[3][2]
Elongation at break%Not documented5.4-9.1 at break (printed XZ, ASTM D638, Stratasys); 1.9-4.3 in ZX; 3DXTech quotes 3 (ISO 527)[3][2]
Flexural strengthMPaNot documented104-116 at break (printed XZ, ASTM D790 Procedure A, Stratasys); 72-98 in ZX; 3DXTech quotes 90 (ISO 178)[3][2]
Flexural modulusMPaNot documented2400-2550 (printed XZ, ASTM D790, Stratasys F900 T16 and T16A) against 2120-2130 in ZX; 3DXTech quotes 2170 (ISO 178)[3][2]
Other impact dataNot documentedIzod notched 88.5-140 J/m XZ against 37-80 J/m ZX; unnotched 647-2260 J/m XZ against 169-633 J/m ZX (printed, ASTM D256/D4812, Stratasys, across three printers and three tips)[3]
Layer adhesion / Z tensileMPaNot documented39-63 at break (printed ZX, ASTM D638, Stratasys); the low end is the F900 T16 baseline, the high end the F3300 N500 hot end[3]
Brittleness1–5Brittle — Proto-pasta describes the filament as more brittle than standard PLA and needing extra care in handling[1]Brittle — snaps with little warning[2]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documentedRockwell M110 / R126 on extruded PEI stock (ASTM D785)[15]
Creep resistance / sustained load1–5Not documentedExcellent — holds load for years. Printed ZX coupons keep 87 % of room-temperature tensile strength at 104 °C and 70 % at 132 °C (ASTM D638); extruded PEI stock is rated 170 °C long-term service[3][15]
Elasticity / flexibility1–5Rigid[1]Rigid[2]
Z strength as % of XY%Not documented56-86 (Stratasys ZX against XZ tensile at break, ASTM D638, across F900/F3300/Fortus 450mc and T16/T20/T40A tips); 58 on the F900 T16 baseline[3]
Thermal Properties
HDT at 0.45 MPa°CNot documented158 (printed XY, ISO 75 at 0.45 MPa, 3DXTech) to 178 (printed XY 178.2 and ZX 178.4, ASTM D648 Method B at 66 psi, Stratasys); moulded 176.9[2][3]
HDT at 1.8 MPa°CNot documented170-173 (printed XY 170.2 and ZX 172.6, ASTM D648 Method B at 264 psi); moulded 172.9[3]
Glass transition (Tg)°CNot documented177 (moulded plaque, ASTM D7426 inflection point, Stratasys); 186 (DSC, 3DXTech)[3][2][16]
Continuous service temperature°CNot documented170 long-term service on extruded PEI stock, converted from 338 °F; 200 short term[15]
Thermal expansion (CTE)µm/m·KNot documented44.9 (printed XY, -50 to 80 °C, ASTM E831), falling to 31.4 over 80-160 °C; ZX gives 44.5 over -50 to 60 °C. Black pigment raises it to 51.9[3]
Flammability / UL 94Not documentedUL 94 V-0 at 1.5 mm on the base resin. Printed parts are tested to 14 CFR 25.853, BSS 7238 and 7239 and AITM 2.0007B and 3.0005 covering 60 s and 12 s vertical burn, 15 s horizontal burn, smoke density, toxic gas emission and OSU heat release[2][3]
Environment & Chemical
UV resistance1–5Not documentedGood — years with some colour shift. 1000 h of QUV cycling to ASTM G154 left printed ZX coupons at 55.5 MPa yield against 56.0 unexposed, with elongation and modulus unchanged[3]
Outdoor durabilityDeliberately rustable — Proto-pasta markets the iron content as oxidising when exposed to moisture[1]Not documented
Electrical & ESD propertiesFerromagnetic: Proto-pasta states it responds to magnets and behaves similarly to pure iron[1]Not documented
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[17]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[17]
Ventilation / filtration requirement1–5Open a window / occasional ventilation[17]Ventilated room or enclosure recommended[17]
Post-Processing
Sanding & machiningPolishing and deliberate rusting are the intended finishes[1]Not documented
Solvents & Solubility
Soluble inChloroform dissolves the PLA matrix and leaves the iron powder behind; laboratory reagent, not workshop stock.[18][1]Chlorinated hydrocarbons — dichloromethane and chloroform — are solvents for polyetherimide. Laboratory reagents.[19][20]
Softened or crazed byAcetone and ethyl acetate plasticise the matrix rather than dissolving it; water attacks the exposed iron.[18][1]Acetone, MEK, benzene, toluene and butyl acetate craze or stress-crack it; alcohols, fuels and dilute acids do not.[20][19]
Solvent welding & smoothing agentNone — PLA has no workshop-safe solvent, and the iron loading blocks the surface flow smoothing needs.[18]Dichloromethane is the only welding route, and it is a controlled carcinogen rather than a workshop material.[19][20]

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. Magnetic Iron PLA — product page and technical data Proto-pasta · 2026-08 · tds
  2. ThermaX PEI 9085 Technical Data Sheet v4 3DXTech · 2026-08 · tds
  3. ULTEM 9085 Resin — FDM Material Data Sheet Stratasys · 2026-04 · tds
  4. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  5. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  6. Kimya PEI-9085 Natural 2.85 mm 500 g igo3d · 2026-08 · vendor
  7. Fiberlogy PEI 9085 Natural, 1.75 mm / 500 g 3DJAKE · 2026-08 · vendor
  8. 3D4Makers product catalogue 3D4Makers · 2026-08 · vendor
  9. IEMAI 3D PEI 9085 3D Printing Filament — store page IEMAI 3D · 2026-08 · vendor
  10. Prusament PEI 1010 Technical Datasheet v1.0 Prusa Polymers · 2024-09 · tds
  11. Prusament PEI 1010 — material page Prusa Polymers · 2026-08 · doc
  12. Composite materials with metal or wood particles Prusa Knowledge Base · 2026-08 · doc
  13. THERMAX PEI 9085 — product page (print recommendations) 3DXTech · 2026-08 · doc
  14. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  15. TECAPEI natural (PEI) — stock shape properties Ensinger · 2026-08 · tds
  16. ThermaX PEI 1010 Technical Data Sheet v4 3DXTech · 2026-08 · tds
  17. 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
  18. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  19. Radel PPSU, Veradel PESU, Acudel modified PPSU Design Guide — environmental stress cracking tables Solvay Specialty Polymers · 2026-08 · tds
  20. Chemical resistance — resistance of Ensinger plastics to chemicals (DIN 50 014, 23/50) Ensinger · 2026-08 · tds