3D Printing InfoFilament comparison
Magnetic vs PPA
Compare printing settings, strength, heat resistance, dated prices and sources.
2 selected · all documented properties
| Property | Magnetic filamentSPECIALTY | PPA (polyphthalamide)PA |
|---|---|---|
| Market snapshot | ||
| Listing priceUSD/kg; dated snapshots | $64.99/kg median; $64.99–$64.99/kg across 1 dated product listings | $45.49/kg median; $45.49–$45.49/kg across 1 dated product listings |
| Identity & Market | ||
| Base polymer / chemistry | PLA loaded with ferromagnetic iron powder, so printed parts respond to magnets[1] | Polyphthalamide — a semi-aromatic polyamide in which aromatic diacid units replace part of the aliphatic backbone; Raise3D and Bambu Lab both label it high-temperature nylon[2][3] |
| Densityg/cm³ | About 1.85 (Proto-pasta manufacturer figure) — 1.5× standard PLA[1] | 1.21 (ISO 1183, Siraya Tech Fibreheart PPA)[4] |
| Typical priceUSD/kg | 1 kg spools cluster near 65[5] | One 1 kg listing on the market, at 45[6] |
| Price range across brandsUSD/kg | 64–70 across formats; 1 kg spool 65, 500 g 70, 2 kg 70[5] | 45 for the only unfilled PPA filament found — Siraya Tech Fibreheart PPA at 1 kg; every other PPA in retail is carbon- or glass-filled[6] |
| Market availability1–5 | Niche, a handful of specialist brands[5] | Special order, 1–2 makers worldwide — Siraya Tech is the only brand found selling unfilled PPA filament[6] |
| Spool sizes & diameters | 1.75 and 2.85 mm; 0.1, 0.5, 1 and 2 kg spools[5] | 1.75 mm, 1 kg[6] |
| Typical applications | Sensor targets, magnetic fixtures, and props that need to stick to a magnet or rust deliberately[1] | Gears, bearings and tooling that must hold load above the reach of PA6 or PA12, and parts exposed to fuels and industrial chemicals[4] |
| Printing Parameters | ||
| Nozzle temperature°C | 192 (Proto-pasta)[1] | 280–300 (Siraya Tech)[4] |
| Bed temperature°C | 60 (Proto-pasta)[1] | 70–80 (Siraya Tech)[4] |
| Enclosure / chamber requirement1–5 | Open frame is fine[1] | Enclosure recommended — Siraya Tech advises an enclosure to hold temperature and limit warping on larger prints[4] |
| Part cooling fan | Not documented | 20–60 % (Siraya Tech)[4] |
| Bed surface & adhesion aid | Not documented | PEI sheet with a glue stick, or a PVP glue coating[4] |
| Maximum volumetric flow (mm³/s; see test conditions)mm³/s | 1.6–2.4 at Proto-pasta's 20–30 mm/s on a 0.4 mm nozzle at 0.2 mm layer[1] | Not documented |
| Overall printing difficulty1–5 | Intermediate — dry filament and a tuned profile; slow, and brittle in filament form[1] | Advanced — enclosure, hardware upgrades, tuning; needs a 300 °C-class hot end and a dry spool[4] |
| Extruder requirement | Proto-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 required1–4 | Brass acceptable; hardened steel for volume work[1] | Brass fine indefinitely — Siraya Tech states a hardened steel nozzle is not needed for the unfilled grade[4] |
| Abrasiveness1–5 | Moderately abrasive — metal fill[1] | Non-abrasive when unfilled[4] |
| Nozzle clog risk1–5 | Moderate — 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[7] | Moderate — needs dry filament and a clean nozzle; Siraya Tech tells users to dry only when moisture symptoms appear, rather than before every print[4] |
| Hotend requirement | Proto-pasta recommends a wear-resistant or larger nozzle for longer service intervals[1] | High-quality metal nozzle, 0.4–1.0 mm; hardened steel not required (Siraya Tech)[4] |
| Moisture Behaviour | ||
| Moisture absorption (hygroscopicity)1–5 | Not documented | High (0.8–2 %) — Siraya Tech publishes 2.59 % by ISO 62 immersion for the unfilled grade; on the equilibrium basis Bambu Lab uses, its 15 % carbon-filled PPA reaches 1.30 % against 2.35 % for the same maker's PA6-CF[4][3][8] |
| Equilibrium moisture content at ~50 % RH% | Not documented | 2.59 by ISO 62 water immersion (Siraya Tech, unfilled) — an immersion figure, not the 25 °C / 55 % RH equilibrium basis the filled grades are quoted on, so the two are not directly comparable[4] |
| Drying temperature & time | Not documented | 80–100 °C for 4–6 h (Siraya Tech)[4] |
| Symptoms when wet | Not documented | Oozing, bubbles and a rough surface finish (Siraya Tech)[4] |
| Effect of moisture on strength | Polymaker rates PLA low-sensitivity and publishes no dry-versus-conditioned figures; absorbed water flashes to steam and shows as bubbling and poor layer adhesion[9] | Siraya Tech publishes dry against saturated for the same grade: tensile 70 → 60 MPa, flexural 114 → 87 MPa, HDT at 1.8 MPa 73.5 → 48.5 °C, while Charpy rises 10 → 14.5 kJ/m²[4][6] |
| Storage requirement | Not documented | Dry box below 15 % RH (Siraya Tech)[4] |
| Mechanical Properties | ||
| Tensile strength (XY)MPa | Not documented | 72 at break (printed, ASTM D638, Siraya Tech); the product page quotes 70 dry and 60 saturated[4][6] |
| Young's modulusMPa | Not documented | 3600 (printed, ASTM D638, Siraya Tech)[4] |
| Elongation at break% | Not documented | 10.5 at break (printed, ASTM D638, Siraya Tech)[4] |
| Flexural strengthMPa | Not documented | 115 (printed, ISO 178, Siraya Tech); 114 dry against 87 saturated on the product page[4][6] |
| Flexural modulusMPa | Not documented | 3350 (printed, ISO 178, Siraya Tech)[4] |
| Charpy impact, notchedkJ/m² | Not documented | 10.1 Charpy (printed, ISO 179, Siraya Tech); the data sheet does not state whether the specimen was notched[4] |
| Brittleness1–5 | Brittle — Proto-pasta describes the filament as more brittle than standard PLA and needing extra care in handling[1] | Moderate — 10.5 % elongation at break puts it between PA6 and the fibre-filled grades[4] |
| Creep resistance / sustained load1–5 | Not documented | Good — Raise3D cites high creep resistance as a reason to choose the PPA matrix over other nylons[2] |
| Elasticity / flexibility1–5 | Rigid[1] | Rigid — 3.6 GPa tensile modulus[4] |
| Wear resistance & friction | Not documented | Siraya Tech describes the unfilled grade as low-friction and self-lubricating, aimed at gears and bearings[4][6] |
| Thermal Properties | ||
| HDT at 0.45 MPa°C | Not documented | 81 dry and 61 saturated (printed, ISO 75 Method B at 0.45 MPa, Siraya Tech)[4] |
| HDT at 1.8 MPa°C | Not documented | 73.5 dry and 48.5 saturated (printed, ISO 75 Method A at 1.8 MPa, Siraya Tech) — unfilled PPA deflects near its Tg; the 190–227 °C figures quoted for PPA are carbon-filled grades[4][3] |
| Glass transition (Tg)°C | Not documented | 80 (ASTM D3418, Siraya Tech)[4] |
| Melting point / Vicat°C | Not documented | 231 melting point (ASTM D3418) and 230 Vicat (ISO 306), Siraya Tech[4] |
| Annealing response | Not documented | Siraya Tech's product page offers annealing for strength while its own data sheet says annealing is not recommended because the print can warp; on its 15 % carbon-filled PPA, annealing lifts HDT at 1.8 MPa from 82.5 to 119 °C[4][6][10] |
| Environment & Chemical | ||
| Outdoor durability | Deliberately rustable — Proto-pasta markets the iron content as oxidising when exposed to moisture[1] | Not documented |
| Chemical resistance | Not documented | Withstands fuels, oils and industrial chemicals; Bambu Lab rates semi-aromatic nylon better than general nylon against weak acids, weak alkalis and most organic solvents[4][3] |
| Water / humidity resistance in service1–5 | Not documented | Absorbs water, properties shift — a saturated specimen loses about 15 % of its tensile strength and 25 °C of heat-deflection temperature[4][6] |
| Electrical & ESD properties | Ferromagnetic: Proto-pasta states it responds to magnets and behaves similarly to pure iron[1] | Not documented |
| Health & Safety | ||
| Fume toxicity1–5 | Low hazard — minimal VOC and particle emission; none of these materials was in the chamber study[11] | Not documented |
| Ventilation / filtration requirement1–5 | Open a window / occasional ventilation[11] | Not documented |
| Post-Processing | ||
| Sanding & machining | Polishing and deliberate rusting are the intended finishes[1] | Not documented |
| Support material pairing | Not documented | Compatible with quick-release support materials (Siraya Tech)[4] |
| Solvents & Solubility | ||
| Soluble in | Chloroform dissolves the PLA matrix and leaves the iron powder behind; laboratory reagent, not workshop stock.[12][1] | Dissolved at 23 °C by formic acid, phenol, m-cresol, 96 % sulphuric acid or hexafluoroisopropanol — all laboratory reagents.[13] |
| Softened or crazed by | Acetone and ethyl acetate plasticise the matrix rather than dissolving it; water attacks the exposed iron.[12][1] | Mineral acids, oxidants, halogens and zinc chloride solutions attack the amide bond; ordinary solvents do not.[13] |
| Solvent welding & smoothing agent | None — PLA has no workshop-safe solvent, and the iron loading blocks the surface flow smoothing needs.[12] | None — nylon's only solvents are formic acid, phenol and HFIP, all of which degrade the part they wet.[13] |
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
- Magnetic Iron PLA — product page and technical data Proto-pasta · 2026-08 · tds
- Raise3D Industrial PPA CF Technical Data Sheet V2.0 Raise3D · 2022-04 · tds
- Bambu Filament Technical Data Sheet V1.0 — PPA-CF Bambu Lab · 2026-08 · tds
- Siraya Tech Fibreheart PPA Technical Data Sheet Siraya Tech · 2026-08 · tds
- Proto-pasta product catalogue Proto-pasta · 2026-08 · vendor
- Siraya Tech Fibreheart PPA Filament — product page Siraya Tech · 2026-08 · vendor
- Composite materials with metal or wood particles Prusa Knowledge Base · 2026-08 · doc
- Bambu Filament Technical Data Sheet V3.0 — PA6-CF Bambu Lab · 2026-08 · tds
- Wet Filament — signs, causes and drying Polymaker Wiki · 2026-08 · doc
- Siraya Tech Fibreheart PPA-CF Technical Data Sheet Siraya Tech · 2026-08 · tds
- 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
- Solubility Study of Ingeo Biopolymer Grades in Common Organic Solvents (NWPD003) NatureWorks · 2019-10 · tds
- Ultramid Nylon Chemical Resistance guide (unmodified PA6 B27E and PA66 A27E) BASF · 2026-08 · tds