Materials / Compare

Plastic Nylon PA66 vs. Plastic PETG

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

Plastic Nylon PA66Bulk polymer (molded or machined)
Plastic PETG3D printed (FDM)
MechanicalPlastic Nylon PA66Plastic PETG
Yield strength85MPa11.84x stronger46.2MPa2
Ultimate tensile strengthnot stated (yield given)46.2MPa2
Flexural strengthnot sourced78.9MPa2
Elongation at break30%13.95x more ductile7.6%2
Young's modulus (stiffness)3GPa11.55x stiffer1.94GPa2
Density1,130kg/m³112% lighter1,270kg/m³2
Strength to weight75.2kN·m/kg2.07x higher36.4kN·m/kg
Stiffness to weight2.65MN·m/kg1.74x higher1.53MN·m/kg
Poisson's ratiobase material0.43not sourced
Shear modulus1.07GPanot sourced
Bulk modulus5GPanot sourced
Speed of sound1,629m/s32% faster1,236m/s
1k10k0.1110100Density (kg/m³)Young's modulus (GPa)Plastic PLAPlastic ABSPlastic TPUPlastic NylonWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic POM/AcetalPlastic Nylon PA6Plastic PEEKPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM PAHT-CFFDM HIPSSLA Resin StandardSLA Resin Tough 2000SLS PA12 NylonDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelConcretePCB Laminate FR-4SiliconCeramic Alumina 96%Ceramic Aluminum NitrideAluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic Nylon PA66Plastic PETG
Stiffness against densityHigher and further left: stiffer for its weight
1k10k101001kDensity (kg/m³)Yield strength (MPa)Plastic PLAPlastic ABSPlastic TPUPlastic NylonRubberWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic POM/AcetalPlastic Nylon PA6Plastic PEEKPlastic PTFEPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM PAHT-CFFDM HIPSSLA Resin StandardSLA Resin Tough 2000SLA Resin Elastic 50ASLS PA12 NylonDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelBrickPCB Laminate FR-4SiliconCeramic Alumina 96%Aluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic Nylon PA66Plastic PETG
Strength against densityHigher and further left: stronger for its weight
ThermalPlastic Nylon PA66Plastic PETG
Thermal conductivity0.33W/m·K11.57x more heat through a finbase material0.21W/m·K4
Thermal expansionlongitudinal98µm/m·K1base material51µm/m·K41.92x less
100 mm part over a 50 °C swing490µm growth255µm growth1.92x less
Specific heat1,700J/kg·K131% higherbase material1,300J/kg·K4
Heats up and cools (diffusivity)0.172mm²/s35% faster0.127mm²/s
Thermal shock resistance57.2W/mnot sourced
Melting pointDSC260°C1not sourced
Glass transitionnot sourced77.4°C2
Max service temperature101°C1HDT 0.455 MPa76.2°C2
1k10k0.1110100Density (kg/m³)Thermal conductivity (W/m·K)Plastic PLAPlastic ABSPlastic NylonRubberWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic POM/AcetalPlastic Nylon PA6Plastic PEEKPlastic PTFEPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM HIPSSLA Resin StandardDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelConcreteBrickPCB Laminate FR-4SiliconCeramic Alumina 96%Ceramic Aluminum NitrideAluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic Nylon PA66Plastic PETG
Thermal conductivity against densityHigher and further left: spreads more heat for its weight
0.111010010100Thermal conductivity (W/m·K)Thermal expansion (µm/m·K)Plastic ABSPlastic NylonWoodAluminumSteelIronTitaniumSteel AISI 1018Stainless Steel 304Stainless Steel 316Aluminum 6061-T6Aluminum 7075-T6Brass C360Copper C110Copper C10100Copper C12200GlassSteel AISI 1045Steel AISI 4340Steel A992Stainless Steel 303Stainless Steel 17-4PHAluminum 2024-T351Aluminum 5052-H32Aluminum 7050-T7451Titanium Ti-6Al-4VBrass C260Nickel Inconel 718Magnesium AZ31B-H24Zinc Zamak 3Plastic ABS (bulk/injection)Plastic PolycarbonatePlastic POM/AcetalPlastic Nylon PA6Plastic PEEKPlastic PTFEPlastic UHMWPEPlastic HDPEPlastic PolypropylenePlastic PMMAFDM ASAFDM PolycarbonateFDM HIPSSLA Resin StandardDMLS AlSi10Mg AluminumDMLS Ti-6Al-4V ELI TitaniumDMLS 316L Stainless SteelDMLS 17-4PH Stainless SteelConcreteBrickPlywoodPCB Laminate FR-4SiliconCeramic Alumina 96%Ceramic Aluminum NitrideAluminum A380Aluminum 6063-T6Aluminum 1100-OAluminum 3003-OAluminum ADC12Magnesium AZ91DSolder SAC305Plastic PBT GF30Plastic PPS GF40Plastic LCP GF30Plastic Nylon PA66Plastic PETG
Thermal expansion against thermal conductivityLower and further right: warps less when heated
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Sources4 documents: BASF, UltiMaker, Covestro, Eastman
Plastic Nylon PA66
BASF Ultramid A3K (PA66, unreinforced injection-moulding grade), Product Information 02/2026, dry values (ISO methods)
Plastic PETG
Ultimaker PETG, 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 v1.00, April 29, 2022.
  1. 1
    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
  2. 2
    Ultimaker PETG Technical Data Sheet, v1.00UltiMakerarchived copyPlastic PETG · Yield strength: typicalPlastic PETG · Ultimate tensile strength: typical, peak stress (= stress at yield)Plastic PETG · Flexural strength: typicalPlastic PETG · Elongation at break: typicalPlastic PETG · Young's modulus (stiffness): typicalPlastic PETG · Density: typicalPlastic PETG · Glass transition: typicalPlastic PETG · Max service temperature: HDT 0.455 MPa (printed specimens)
  3. 3
    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)
  4. 4
    Eastar Copolyester 6763 Product Data SheetEastmanPlastic PETG · Thermal conductivity: base material: Eastman Eastar Copolyester 6763 (PETG), typicalPlastic PETG · Thermal expansion: base material: Eastman Eastar Copolyester 6763 (PETG), typicalPlastic PETG · Specific heat: base material: Eastman Eastar Copolyester 6763 (PETG), DSC at 60 °C (lowest temperature listed)

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.

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

Questions

Mechanical

Is Plastic Nylon PA66 stronger than Plastic PETG?

Plastic Nylon PA66 is stronger: its yield strength is 85 MPa against 46.2 MPa for Plastic PETG (1.84x).

Which is lighter, Plastic Nylon PA66 or Plastic PETG?

Plastic Nylon PA66 is lighter: 1,130 kg/m³ against 1,270 kg/m³ for Plastic PETG.

Which is stiffer, Plastic Nylon PA66 or Plastic PETG?

Plastic Nylon PA66 is stiffer: Young's modulus 3 GPa against 1.94 GPa for Plastic PETG, so the same part in Plastic Nylon PA66 deflects less under the same load.

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

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 bePlastic Nylon PA66Plastic PETG
Stiff rod or tie (tension)lighter1.74x heavier
Stiff beam (bending)lighter40% heavier
Stiff panel or platelighter30% heavier
Strong rod or tielighter2.07x heavier
Strong beamlighter1.69x heavier
Strong panel or platelighter1.52x heavier

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, Plastic Nylon PA66 or Plastic PETG?

Plastic Nylon PA66 stretches further before it breaks: 30% elongation at break against 7.6% for Plastic PETG.

Thermal

Which conducts heat better, Plastic Nylon PA66 or Plastic PETG?

Plastic Nylon PA66 conducts heat better: 0.33 W/m·K against 0.21 W/m·K for Plastic PETG.

Which expands less with temperature?

Plastic PETG expands less: 51 µm/m·K against 98 µm/m·K for Plastic Nylon PA66.

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