3D Printing Info

Filament comparison

PLA Metal vs TPU 85A

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

Metal-filled PLA guideTPU 85A guide

2 selected · all documented properties

Open these two in the interactive comparisonMore PLA Metal comparisonsMore TPU 85A comparisons
PLA Metal vs TPU 85A — documented properties and sources
PropertyMetal-filled PLAPLATPU 85AFLEX
Market snapshot
Listing priceUSD/kg; dated snapshots$79.69/kg median; $24.99–$94.99/kg across 6 dated product listings$89.89/kg median; $31.99–$106.05/kg across 6 dated product listings
Identity & Market
Base polymer / chemistryPLA loaded with real metal powder — bronze, copper, steel or iron. Bambu Lab's PLA Sparkle TDS states it has "metal particles included in its composition"; its separately sold PLA Metal does not, and the store page says so explicitly[1][2][3][4][5][6]Soft thermoplastic polyurethane at 82–85 Shore A[7][8][9]
Densityg/cm³1.26 (Bambu Lab Sparkle, a trace-metal glitter grade) up to 3.9–4.0 for colorFabb bronze and copper and 2.3 for Proto-pasta steel, ISO 1183[4][1][2][10]1.11 (BASF Ultrafuse 85A) to 1.19 (NinjaFlex 85A), ISO 1183 / ASTM D792[9][7]
Typical priceUSD/kg1 kg spools cluster near 78[11][12][3]1 kg-equivalent spools span 32–106; the middle of the market is about 90[13][14][7]
Price range across brandsUSD/kg25–95 across brands; Bambu Lab Sparkle 25, Proto-pasta iron 65, colorFabb bronze and copper 84, Proto-pasta steel 95[11][3][12][10]32–106 across brands; Siraya Tech Flex TPU 85A 32 at 1 kg, add:north TPU Pro Matte 85A 72, Recreus Filaflex 82A 90 at 500 g, Proto-pasta Clear Flexible TPU 90, 3DXTech 3DXFLEX 85A 96, NinjaTek NinjaFlex 106[15][13][14][16][7]
Market availability1–5Available from several mainstream brands[12][3][10][11]Available from several mainstream brands[13][15]
Spool sizes & diameters1.75 and 2.85 mm; 0.1, 0.5, 0.75, 1 and 1.5 kg spools[15][12]1.75, 2.85 and 3 mm; 0.5, 1 and 2 kg spools[13][15][7]
Typical applicationsDecorative castings and props that are polished or left to patinate; the density gives prints a metallic heft[1][3]Soft-touch grips, seals, wearables and anything that must compress and rebound[7][8]
Printing Parameters
Nozzle temperature°C195–220 (colorFabb bronze and copper); 192 (Proto-pasta iron); 198 (Proto-pasta steel); 190–230 (Bambu Lab Sparkle)[1][3][10][4]200–220 (BASF Ultrafuse 85A, 210 typical)[9]
Bed temperature°C50–60 (colorFabb, Proto-pasta); 35–45 (Bambu Lab)[1][3][4]40 (BASF Ultrafuse 85A)[9]
Enclosure / chamber requirement1–5Open frame is fine[1]Open frame is fine[9]
Part cooling fanOn (colorFabb copper); 0–100 % (colorFabb bronze)[1][2]Not documented
Bed surface & adhesion aidGlass plate with glue stick or tape (colorFabb)[1][2]PEI sheet or painter's tape; Polymaker warns TPU can over-stick and advises a glue stick as a release agent[17][18]
Maximum volumetric flow (mm³/s; see test conditions)mm³/s1.6–2.4 at Proto-pasta's 20–30 mm/s for iron and steel, 3.2–8 at colorFabb's 40–100 mm/s, on a 0.4 mm nozzle at 0.2 mm layer[3][10][1][19]1.2–3.2 at the 15–40 mm/s BASF specifies on a 0.4 mm nozzle at 0.2 mm layer[9]
Warping tendency1–5Not documentedNone[9]
Bed-adhesion difficulty1–5Not documentedSticks to anything — Recreus states its 82A grade has excellent bed adhesion without a heated bed or additives[8]
Stringing / oozing tendency1–5Not documentedHigh — drying plus tuning needed[20][18]
Overall printing difficulty1–5Intermediate — dry filament and a tuned profile; brittle in filament form and slow to print[3][10]Advanced — enclosure, hardware upgrades, tuning; at this hardness the filament will not push through a Bowden tube[7][8]
Extruder requirementProto-pasta advises an extrusion width 0.05 mm larger than the nozzle and warns that feeding is inconsistent below 0.4 mm and on Bowden machines[3][10]Direct drive only. NinjaTek calls its 85A grade ideal for direct-drive extruders and Recreus specifies direct-drive printers for 82A; BASF caps print speed at 15–40 mm/s with a nozzle of 0.4 mm or larger[7][8][9]
Hardware Wear & Reliability
Nozzle hardness required1–4Brass acceptable; hardened steel for volume work[3][10]Brass fine indefinitely[21]
Abrasiveness1–5Moderately abrasive — metal fill[3][10]Non-abrasive[21]
Nozzle clog risk1–5Moderate — needs dry filament and a clean nozzle[10]High — jams from moisture, heat creep or particles[20][18]
Heat-creep / jam sensitivity1–5Not documentedVery high — softens in the cold zone readily; soft filament buckles between the drive gear and the melt zone[18][7]
Hotend requirementProto-pasta recommends a wear-resistant or larger nozzle for longer service intervals[3][10]No special hot-end required, but a direct-drive extruder is (Simplify3D)[17]
Other hardware wearProto-pasta warns of more frequent nozzle replacement and first-layer adjustment[3][10]Not documented
Moisture Behaviour
Moisture absorption (hygroscopicity)1–5Moderate — the PLA matrix takes up 0.40–0.51 % saturated; the metal powder itself does not absorb water[22][23]Moderate — NinjaTek measures 0.22 % in 24 h (ASTM D570) and BASF specifies a 70 °C dry for at least 5 h[7][9]
Equilibrium moisture content at ~50 % RH%Not documented0.22 after 24 h water immersion (NinjaFlex 85A, ASTM D570) — an immersion figure, not an equilibrium moisture content at 50 % RH[7]
Drying temperature & timeNot documented70 °C for at least 5 h in a hot-air dryer or vacuum oven (BASF)[9]
Symptoms when wetNot documentedBubbling and popping at the nozzle, stringing and a rough surface[20]
Effect of moisture on strengthPolymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures for this grade; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[20]Polymaker groups TPU with the highly hygroscopic materials; wet TPU prints with poor layer adhesion and weak, brittle layers[20]
Storage requirementNot documentedSealed with desiccant; often kept in a dryer during the print[20]
Mechanical Properties
Tensile strength (XY)MPa25 (colorFabb copper) and 30 (colorFabb bronze), ISO 527-1A; Bambu Lab Sparkle 39 ± 3 printed XY, ISO 527[1][2][4]26 ultimate (NinjaFlex 85A, ASTM D638)[7]
Young's modulusMPa1940 ± 230 printed XY, ISO 527 (Bambu Lab Sparkle)[4]12 (NinjaFlex 85A, ASTM D638) — two orders of magnitude below any rigid filament; NinjaTek's 95A Cheetah reaches 26 by the same method[7][24]
Elongation at break%3–10 (colorFabb copper) and 5–10 (colorFabb bronze), ISO 527-1A; 11.7 for Bambu Lab Sparkle printed XY[1][2][4]650 at break (Filaflex 82A) and 660 (NinjaFlex 85A); BASF measures 600 in XY and 320 in ZX[8][7][9]
Flexural strengthMPa75 ± 4 printed XY, ISO 178 (Bambu Lab Sparkle)[4]Not documented
Flexural modulusMPa2350 ± 140 printed XY, ISO 178 (Bambu Lab Sparkle)[4]Not documented
Charpy impact, notchedkJ/m²23.2 ± 2.4 printed XY, ISO 179, notched (Bambu Lab Sparkle)[4]Not documented
Other impact dataIzod notched 4.5 kJ/m² for colorFabb bronzeFill and 10 kJ/m² for copperFill (ISO 180); Charpy unnotched 66.5 kJ/m² for Bambu Lab Sparkle[1][2][4]Not documented
Layer adhesion / Z tensileMPa32 ± 2 printed Z, ISO 527 (Bambu Lab Sparkle)[4]Not documented
Brittleness1–5Brittle — Proto-pasta describes both its iron and steel grades as more brittle than standard PLA in filament form[3][10]Very ductile — bends far before failing[7]
Hardness (scale-specific)Shore A / Shore D / RockwellNot documented29 Shore D / 85 Shore A (BASF Ultrafuse 85A, ISO 7619-1); 85 Shore A (NinjaFlex, ASTM D2240); 82 A nominal for Filaflex[7][9][8]
Creep resistance / sustained load1–5Poor — no metal-filled creep test; plain printed PLA sagged from 12 to 16.2–21.8 mm over 5 days at 1.25 kg[25][26][27]Poor — no 85A creep test; a printed 95A TPU bar crept from 74.5 to 82.7 mm over 5 days at 1.25 kg, and softer grades creep more[28]
Fatigue / repeated-flex resistance1–5Poor — no grade-specific S-N curve; plain printed PLA ran 38 000–49 000 cycles at 30 % of tensile strength and Proto-pasta describes its iron and steel grades as more brittle than standard PLA[29][3][10]Excellent — living hinges viable[18]
Elasticity / flexibility1–5Rigid[4]Rubbery / highly elastic[7][8]
Z strength as % of XY%82 by tensile (printed, Bambu Lab Sparkle)[4]53 — BASF measures 320 % elongation at break in ZX against 600 % in XY[9]
Wear resistance & frictionNot documentedAbrasion 0.08 g mass loss over 10 000 cycles (NinjaFlex, ASTM D4060); 82 mm³ (BASF, ISO 4649)[7][9]
Thermal Properties
HDT at 0.45 MPa°C55 (ISO 75, 0.45 MPa, Bambu Lab Sparkle)[4]Not documented
HDT at 1.8 MPa°C53 (ISO 75, 1.8 MPa, Bambu Lab Sparkle)[4]Not documented
Glass transition (Tg)°C56 (DSC, Bambu Lab Sparkle)[4]Not documented
Melting point / Vicat°C156 peak melt (DSC, Bambu Lab Sparkle)[4]216 melting (NinjaFlex 85A, DSC)[7]
Environment & Chemical
UV resistance1–5Degrades within weeks outdoors[30]Good — years with some colour shift; Polymaker lists UV exposure among the conditions TPU withstands[18]
Outdoor durabilityProto-pasta markets its iron grade as rustable — the iron oxidises deliberately when exposed to moisture[3]Not documented
Chemical resistanceNot documentedWithstands industrial solvents and UV exposure (Polymaker)[18]
Food contactNot documentedNot food safe without specific certification (Polymaker)[18]
Biodegradability / compostabilityNot documentedNot biodegradable[18]
RecyclabilityNot documentedNot accepted in household plastic collection[18]
Electrical & ESD propertiesProto-pasta magnetic iron PLA is ferromagnetic and responds to magnets[3]Not documented
Health & Safety
Fume toxicity1–5Low hazard — minimal VOC and particle emission[31]Low hazard — minimal VOC and particle emission; TPU was not among the nine filaments in the chamber study[31]
Ventilation / filtration requirement1–5None needed in a normal room[31]Open a window / occasional ventilation[31]
Post-Processing
Sanding & machiningPolishing is the intended finish — colorFabb and Proto-pasta both sell these grades to be sanded and buffed to a metallic shine[1][2][10]Difficult to sand or smooth; Polymaker limits post-processing to trimming or tumbling[18]
Gluing & solvent weldingNot documentedCyanoacrylate bonds TPU; no common solvent welds it[18]
Vapour / chemical smoothingNot documentedNo practical vapour smoothing[18]
Support material pairingNot documentedPolymaker warns TPU supports are often very difficult to remove[18]
Dimensional accuracy & detailcolorFabb notes the metal fill increases die swell, so flow needs raising above plain PLA[2]Not documented
Solvents & Solubility
Soluble inChloroform dissolves the PLA matrix (10 % w/v, 2–4 h at 23 °C) and leaves the filler as loose sludge; laboratory reagent.[32]DMF, DMSO, NMP and THF dissolve TPU; acetone, MEK and cyclohexanone are partial solvents. All laboratory reagents.[33]
Softened or crazed byAcetone, ethyl acetate and toluene plasticise the matrix but dissolve <1 % even at 65 °C; acetone submersion crazes parts.[32][34]Toluene and benzene swell it up to +50 % by weight at 23 °C; esters swell it severely; ethanol and IPA soften it.[33]
Solvent welding & smoothing agentChloroform vapour attacks only the resin fraction, so the filler is left standing proud; no workshop-safe agent exists.[35][34]None practical — the true solvents (DMF, THF, NMP) are laboratory reagents and leave the joint swollen and weak.[33]

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. bronzeFill technical data sheet colorFabb · 2026-08 · tds
  2. copperFill technical data sheet colorFabb · 2026-08 · tds
  3. Magnetic Iron PLA — product page and technical data Proto-pasta · 2026-08 · tds
  4. Bambu Filament Technical Data Sheet — PLA Sparkle Bambu Lab · 2026-08 · tds
  5. PLA Metal — product page Bambu Lab US Store · 2026-08 · vendor
  6. Bambu Filament Technical Data Sheet V3.0 — PLA Metal Bambu Lab · 2026-08 · tds
  7. NinjaFlex 85A Technical Specifications NinjaTek · 2026-08 · tds
  8. Filaflex 82A product page (Shore hardness and elongation) Recreus · 2026-08 · vendor
  9. Ultrafuse TPU 85A Technical Data Sheet (Version 3.0) BASF Forward AM · 2022-08 · tds
  10. Stainless Steel PLA — product page and technical data Proto-pasta · 2026-08 · tds
  11. PLA Sparkle — product page Bambu Lab US Store · 2026-08 · vendor
  12. bronzeFill — product page colorFabb US · 2026-08 · vendor
  13. 3DXTech product catalogue 3DXTech · 2026-08 · vendor
  14. Siraya Tech Flex TPU 85A Filament — product page Siraya Tech · 2026-08 · vendor
  15. Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
  16. add:north TPU Pro Matte 85A product page add:north · 2026-08 · vendor
  17. Flexible (TPE/TPU) — Ultimate 3D Printing Materials Guide Simplify3D · 2026-08 · doc
  18. TPU — material basics Polymaker Wiki · 2026-08 · doc
  19. Max volumetric speed Prusa Knowledge Base · 2026-08 · doc
  20. Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
  21. Extrudr Product Catalogue (DURAPRO PA12 data block) Extrudr · 2025-03 · tds
  22. Bambu Filament Technical Data Sheet V3.0 — PLA Basic Bambu Lab · 2026-08 · tds
  23. PolyLite PLA Technical Data Sheet V5.4 Polymaker · 2024-11 · tds
  24. NinjaTek technical specs comparison chart (Cheetah, NinjaFlex, Armadillo, Alloy 910, Nylon 645) NinjaTek · 2026-08 · tds
  25. BambuLab PLA Basic vs PLA Tough vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  26. Polymaker PLA Pro vs PLA-CF — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  27. Carbon Fiber PLA vs META-PLA vs PLA+ vs PLA by Sunlu — results spreadsheet My Tech Fun (Igor Gaspar) · 2026-08 · test
  28. BambuLab TPU 95A HF vs Qidi TPU 95A HF — results spreadsheet My Tech Fun (Igor Gaspar) · 2024-02 · test
  29. Mechanical Properties of Additively Manufactured Polymeric Materials — PLA and PETG — For Biomechanical Applications Polymers 16(13):1868 · 2024-06 · paper
  30. PLA — material guide Prusa Knowledge Base · 2026-08 · doc
  31. 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
  32. Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
  33. Elastollan — Chemical properties: swelling and chemical resistance BASF · 2026-08 · tds
  34. Improve your 3D prints with chemical smoothing Prusa Research · 2026-08 · doc
  35. Effect of vapour smoothing in trichloromethane on 3D printed PLA — surface, mechanical and chemical structure Pitale, Keche & Chopra, Engineering Research Express 6(4) 045579 · 2024-12 · paper