FDM Polycarbonate vs. Plastic Nylon PA66

Compare FDM Polycarbonate vs. Plastic Nylon PA66 strength, stiffness, weight and thermal properties.

Plastic Nylon PA66Bulk polymer (molded or machined)

Mechanical	FDM Polycarbonate	Plastic Nylon PA66
Yield strength	53.3MPa1	85MPa21.59x stronger
Ultimate tensile strength	53.3MPa1	not stated (yield given)
Flexural strength	89.4MPa1	not sourced
Elongation at break	9.2%1	30%23.26x more ductile
Young's modulus (stiffness)	2.39GPa1	3GPa225% stiffer
Density	range1,180–1,200kg/m³1	1,130kg/m³2
Strength to weight	44.8kN·m/kg	75.2kN·m/kg1.68x higher
Stiffness to weight	2.01MN·m/kg	2.65MN·m/kg32% higher
Poisson's ratio	base material0.383	base material0.44
Shear modulus	0.867GPa	1.07GPa24% stiffer in shear
Bulk modulus	3.33GPa	5GPa1.5x higher
Speed of sound	1,418m/s	1,629m/s15% faster

Stiffness against densityHigher and further left: stiffer for its weight

Strength against densityHigher and further left: stronger for its weight

Thermal	FDM Polycarbonate	Plastic Nylon PA66
Thermal conductivity	base material0.2W/m·K5	0.33W/m·K21.65x more heat through a fin
Thermal expansion	base material65µm/m·K51.51x less	longitudinal98µm/m·K2
100 mm part over a 50 °C swing	325µm growth1.51x less	490µm growth
Specific heat	not sourced	1,700J/kg·K2
Heats up and cools (diffusivity)	not sourced	0.172mm²/s
Thermal shock resistance	42.5W/m	57.2W/m35% more resistant
Melting point	not sourced	DSC260°C2
Glass transition	108°C1	not sourced
Max service temperature	HDT 0.455 MPa105°C1	101°C2

Thermal conductivity against densityHigher and further left: spreads more heat for its weight

Thermal expansion against thermal conductivityLower and further right: warps less when heated

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Sources5 documents: UltiMaker, BASF, Covestro

FDM Polycarbonate: Ultimaker PC, 3D-printed specimens, XY (flat); Ultimaker S5 Pro, engineering intent profile, 0.15 mm layer height, AA 0.4 print core, 100% infill, Cura 4.9, printed one-at-a-time, conditioned >=24 h at room temperature. TDS (file v5.00), April 20, 2022.
Plastic Nylon PA66: BASF Ultramid A3K (PA66, unreinforced injection-moulding grade), Product Information 02/2026, dry values (ISO methods)

1
Ultimaker PC Technical Data Sheet, v5.00UltiMakerarchived copyFDM Polycarbonate · Yield strength: typicalFDM Polycarbonate · Ultimate tensile strength: typical, peak stress (= stress at yield)FDM Polycarbonate · Flexural strength: typicalFDM Polycarbonate · Elongation at break: typicalFDM Polycarbonate · Young's modulus (stiffness): typicalFDM Polycarbonate · Density: rangeFDM Polycarbonate · Glass transition: typicalFDM Polycarbonate · Max service temperature: HDT 0.455 MPa (printed specimens)
2
Ultramid A3K Product InformationBASFPlastic Nylon PA66 · Yield strength: typical, dryPlastic Nylon PA66 · Elongation at break: nominal strain at break, dryPlastic Nylon PA66 · Young's modulus (stiffness): typical, dryPlastic Nylon PA66 · Density: typicalPlastic Nylon PA66 · Thermal conductivity: typicalPlastic Nylon PA66 · Thermal expansion: longitudinal, 23-55 °CPlastic Nylon PA66 · Specific heat: typicalPlastic Nylon PA66 · Melting point: DSCPlastic Nylon PA66 · Max service temperature: IEC 60216 temperature index, 20000 h
3
Engineering Polymers Part and Mold Design: Thermoplastics, A Design GuideCovestroarchived copyFDM Polycarbonate · Poisson's ratio: base material: polycarbonate family typical (Covestro Part and Mold Design guide, Table 3-1)
4
Engineering Polymers Part and Mold Design: Thermoplastics, A Design GuideCovestroPlastic Nylon PA66 · Poisson's ratio: base material: unfilled polyamide (PA), conditioned, maker design-guide family value (Covestro Table 3-1)
5
Makrolon 2405 Technical Data SheetCovestroFDM Polycarbonate · Thermal conductivity: base material: Covestro Makrolon 2405 injection-molding PC, typical, through-plane, 23 °CFDM Polycarbonate · Thermal expansion: base material: Covestro Makrolon 2405 injection-molding PC, typical, 23-55 °C, parallel

Each number points to the document that states it, with the exact basis. Values without a number are computed from the sourced ones. "Not sourced" means no citable source states it (or only a specification minimum); figures computed from it are left out too.

FDM Polycarbonate is 3D printed: its properties depend on build direction and print settings; these are typical values.

Questions

Mechanical

Is FDM Polycarbonate stronger than Plastic Nylon PA66?

Plastic Nylon PA66 is stronger: its yield strength is 85 MPa against 53.3 MPa for FDM Polycarbonate (1.59x).

Which is lighter, FDM Polycarbonate or Plastic Nylon PA66?

Plastic Nylon PA66 is lighter: 1,130 kg/m³ against 1,190 kg/m³ for FDM Polycarbonate.

Which is stiffer, FDM Polycarbonate or Plastic Nylon PA66?

Plastic Nylon PA66 is stiffer: Young's modulus 3 GPa against 2.39 GPa for FDM Polycarbonate, so the same part in Plastic Nylon PA66 deflects less under the same load.

Which is lighter for the same job, FDM Polycarbonate or Plastic Nylon PA66?

For the same stiffness or strength: Plastic Nylon PA66 is lighter for a stiff rod or tie (tension), stiff beam (bending), stiff panel or plate, strong rod or tie, strong beam, strong panel or plate.

Part that must be	FDM Polycarbonate	Plastic Nylon PA66
Stiff rod or tie (tension)	32% heavier	lighter
Stiff beam (bending)	18% heavier	lighter
Stiff panel or plate	14% heavier	lighter
Strong rod or tie	1.68x heavier	lighter
Strong beam	44% heavier	lighter
Strong panel or plate	33% heavier	lighter

For the same stiffness or strength, mass scales with density over stiffness (or strength) raised to a power set by how the part is loaded: 1 for a rod in tension, 1/2 for a beam in bending, 1/3 for a panel (the standard material-selection indices).

Which is more ductile, FDM Polycarbonate or Plastic Nylon PA66?

Plastic Nylon PA66 stretches further before it breaks: 30% elongation at break against 9.2% for FDM Polycarbonate.

Thermal

Which conducts heat better, FDM Polycarbonate or Plastic Nylon PA66?

Plastic Nylon PA66 conducts heat better: 0.33 W/m·K against 0.2 W/m·K for FDM Polycarbonate.

Which expands less with temperature?

FDM Polycarbonate expands less: 65 µm/m·K against 98 µm/m·K for Plastic Nylon PA66.